Capozide

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Capozide

Classes

Angiotensin Converting Enzyme Inhibitor/ACEIs and Diuretic Combinations

Administration
Oral Administration

Take one hour before meals. Captopril absorption is reduced 30—40% by food.

Adverse Reactions
Severe

peptic ulcer / Delayed / 0.5-2.0
agranulocytosis / Delayed / Incidence not known
hemolytic anemia / Delayed / Incidence not known
aplastic anemia / Delayed / Incidence not known
pancytopenia / Delayed / Incidence not known
vasculitis / Delayed / Incidence not known
pemphigus / Delayed / Incidence not known
toxic epidermal necrolysis / Delayed / Incidence not known
Stevens-Johnson syndrome / Delayed / Incidence not known
exfoliative dermatitis / Delayed / Incidence not known
bronchospasm / Rapid / Incidence not known
hyperkalemia / Delayed / Incidence not known
glomerulonephritis / Delayed / Incidence not known
interstitial nephritis / Delayed / Incidence not known
renal tubular necrosis / Delayed / Incidence not known
renal failure (unspecified) / Delayed / Incidence not known
azotemia / Delayed / Incidence not known
anuria / Delayed / Incidence not known
oliguria / Early / Incidence not known
nephrotic syndrome / Delayed / Incidence not known
visual impairment / Early / Incidence not known
angioedema / Rapid / Incidence not known
anaphylactoid reactions / Rapid / Incidence not known
hepatic failure / Delayed / Incidence not known
hepatic necrosis / Delayed / Incidence not known
pancreatitis / Delayed / Incidence not known
teratogenesis / Delayed / Incidence not known
ocular hypertension / Delayed / Incidence not known
skin cancer / Delayed / Incidence not known

Moderate

erythema / Early / 4.0-7.0
constipation / Delayed / 0.5-2.0
dyspnea / Early / 0.5-2.0
sinus tachycardia / Rapid / 1.0-1.0
palpitations / Early / 1.0-1.0
chest pain (unspecified) / Early / 1.0-1.0
angina / Early / 1.0-1.0
neutropenia / Delayed / Incidence not known
thrombocytopenia / Delayed / Incidence not known
leukopenia / Delayed / Incidence not known
sialadenitis / Delayed / Incidence not known
glossitis / Early / Incidence not known
eosinophilia / Delayed / Incidence not known
pneumonitis / Delayed / Incidence not known
hypokalemia / Delayed / Incidence not known
hypovolemia / Early / Incidence not known
orthostatic hypotension / Delayed / Incidence not known
hypotension / Rapid / Incidence not known
cholestasis / Delayed / Incidence not known
hepatitis / Delayed / Incidence not known
jaundice / Delayed / Incidence not known
elevated hepatic enzymes / Delayed / Incidence not known
hyperbilirubinemia / Delayed / Incidence not known
impotence (erectile dysfunction) / Delayed / Incidence not known
gout / Delayed / Incidence not known
nephrolithiasis / Delayed / Incidence not known
hyperuricemia / Delayed / Incidence not known
hypomagnesemia / Delayed / Incidence not known
hypophosphatemia / Delayed / Incidence not known
hypercalcemia / Delayed / Incidence not known
glycosuria / Early / Incidence not known
hyperglycemia / Delayed / Incidence not known
hypertriglyceridemia / Delayed / Incidence not known
hypercholesterolemia / Delayed / Incidence not known
blurred vision / Early / Incidence not known
xanthopsia / Delayed / Incidence not known
myopia / Delayed / Incidence not known

Mild

maculopapular rash / Early / 4.0-7.0
pruritus / Rapid / 2.0-7.0
dysgeusia / Early / 2.0-4.0
diarrhea / Early / 0.5-2.0
anorexia / Delayed / 0.5-2.0
abdominal pain / Early / 0.5-2.0
xerostomia / Early / 0.5-2.0
vomiting / Early / 0.5-2.0
nausea / Early / 0.5-2.0
cough / Delayed / 0.5-2.0
flushing / Rapid / 0-1.0
dyspepsia / Early / Incidence not known
photosensitivity / Delayed / Incidence not known
alopecia / Delayed / Incidence not known
myalgia / Early / Incidence not known
arthralgia / Delayed / Incidence not known
urticaria / Rapid / Incidence not known
fever / Early / Incidence not known
muscle cramps / Delayed / Incidence not known
weakness / Early / Incidence not known
rhinitis / Early / Incidence not known
dizziness / Early / Incidence not known
syncope / Early / Incidence not known
headache / Early / Incidence not known
fatigue / Early / Incidence not known

Boxed Warning
Pregnancy

Captopril; hydrochlorothiazide is classified as FDA pregnancy risk category C in the first trimester and D in the second and third trimester. Based on the results from one large study, first trimester use of thiazide and related diuretics may increase the risk for congenital defects (pregnancy category D). In addition to malformations, other fetal risks associated with thiazide use during pregnancy include hypoglycemia, thrombocytopenia, hyponatremia, hypokalemia, and death from maternal complications. ACE inhibitors have been associated with fetal and neonatal morbidity and mortality when administered to pregnant women. In women planning to become pregnant, ACE inhibitors should not be used. Women of child-bearing age should be made aware of the potential risk and ACE inhibitors should only be given after careful counseling and consideration of individual risks and benefits. When pregnancy is detected, ACE inhibitors should be discontinued as soon as possible and monitoring of the fetal development should be performed on a regular basis. Rarely (probably less often than once per every thousand pregnancies), no alternative to ACE inhibitors will be found. In these rare cases, the pregnant women should be apprised of the potential hazards to their fetuses, and serial ultrasound examinations should be performed to assess the intraamniotic environment. The reported adverse fetal and neonatal effects (e.g., hypotension, neonatal skull hypoplasia and craniofacial deformation, fetal limb contractures, hypoplastic lung development, anuria, oligohydramnios, reversible or irreversible renal failure, and death) have been reported during ACE inhibitor exposure during the second and third trimesters. In addition, an observational study based on Tennessee Medicaid data reported that the risk of congenital malformations is significantly increased during first-trimester exposure to ACE inhibitors. However, a much larger observational study (n = 465,754) found that the risk of birth defects was similar in infants exposed to ACE inhibitors during the first trimester, in infants exposed to other antihypertensives during the first trimester, and in those whose mothers were hypertensive but were not treated. Infants born to mothers with hypertension, either treated or untreated, had a higher risk of birth defects than those born to mothers without hypertension. The authors concluded that the presence of hypertension likely contributed to the development of birth defects rather than the use of medications. Further evaluation of teratogenicity data associated with ACE inhibitor exposure during pregnancy is ongoing.

Common Brand Names

Capozide

Dea Class

Rx

Description

Combination ACE inhibitor and thiazide diuretic; usually given 2—3 times daily; additive efficacy in HTN; counters the potassium loss from HCTZ; more effective than ACE monotherapy in black patients; captopril contains a sulfhydryl group and is shortest-acting.

Dosage And Indications
For the treatment of hypertension.
NOTE: Individualize the dosage by titration of the separate components. If the optimal dose corresponds to the ratio contained in the combination formulation, this product can be used for convenient dosing.
Oral dosage Adults and Adolescents

Initially, one tablet of captopril; hydrochlorothiazide 25/15 mg PO once daily. Captopril; hydrochlorothiazide may be substituted for the previously titrated individual components. Alternatively, a patient whose blood pressure is not adequately controlled with either captopril or hydrochlorothiazide (HCTZ) monotherapy may be started on captopril; hydrochlorothiazide. Titrate interval and/or the dose of the individual components based on clinical response. Captopril; hydrochlorothiazide is usually dosed 2—3 times daily. The maximum antihypertensive effects of captopril in combination with HCTZ does not occur for 6—8 weeks; therefore dosage adjustments should generally be made at 6 week intervals, unless the clinical situation warrants more rapid adjustment. The usual maintenance dose range for captopril in hypertension is usually 25 to 50 mg PO 2—3 times daily. Hydrochlorothiazide is usually administered in dosages of 12.5 to 50 mg/day PO once daily.

Adults with coexisting hypovolemia, hyponatremia, heart failure or left ventricular dysfunction

Before utilizing the combination product, it is prudent to first titrate the captopril dosage separately, initially starting from a reduced initial dosage of 6.25—12.5 mg PO given 2—3 times daily, and increasing slowly up to the maximum dosage of 50 mg PO three times daily. Correct volume and/or sodium depletion prior to administration of captopril; hydrochlorothiazide therapy. 

Geriatric

See adult dosage. Greater sensitivity to the effects of captopril and hydrochlorothiazide is possible. Dosage should be adjusted based on clinical response.

Children

Safety and efficacy have not been established. See Dosage sections of the Captopril and Hydrochlorothiazide monographs for dosage guidelines to titrate the individual components when indicated. captopril; hydrochlorothiazide may be substituted for the previously titrated individual components when the optimal dosage corresponds to the ratio contained in one of the combination drug formulations.

Dosing Considerations
Hepatic Impairment

Hydrochlorothiazide should be used with caution in patients with hepatic disease since alterations of fluid and electrolyte balance may precipitate hepatic coma in some patients. No dosage adjustments are recommended for captopril in patient with hepatic impairment.

Renal Impairment

CrCl > 50 mL/min: No dosage adjustment is necessary.
CrCl 30—50 mL/min: Reduce the dosage of the captopril component by 25% or extend the dosing interval to every 12 to 18 hours.
CrCl < 30 mL/min: Combination therapy with captopril and hydrochlorothiazide is not recommended. Thiazide diuretics are not effective in this setting.
 
Intermittent hemodialysis
Combination therapy with hydrochlorothiazide is not recommended in patients with CrCl < 30 mL/min. Thiazide diuretics are not effective in this setting.

Drug Interactions

Acarbose: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) Opiate agonists may potentiate orthostatic hypotension when used concurrently with thiazide diuretics.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetaminophen; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetaminophen; Dichloralphenazone; Isometheptene: (Major) Isometheptene has sympathomimetic properties. Patients taking antihypertensive agents may need to have their therapy modified. Careful blood pressure monitoring is recommended. (Major) Isometheptene has sympathomimetic properties. Patients taking antihypertensive agents may need to have their therapy modified. Careful blood pressure monitoring is recommended.
Acetaminophen; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Acetaminophen; Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Acetaminophen; Oxycodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and oxycodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Acetaminophen; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Acetaminophen; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acetazolamide: (Moderate) Acetazolamide promotes electrolyte excretion including hydrogen ions, sodium, and potassium. It can enhance the sodium depleting effects of other diuretics when used concurrently. Pre-existing hypokalemia and hyperuricemia can also be potentiated by carbonic anhydrase inhibitors. Monitor serum potassium to determine the need for potassium supplementation and alteration in drug therapy.
Aclidinium; Formoterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Acrivastine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Albuterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Albuterol; Budesonide: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Aldesleukin, IL-2: (Moderate) Angiotensin converting enzyme inhibitors, like other antihypertensive agents, may potentiate the hypotension seen with aldesleukin, IL 2. (Moderate) Thiazide diuretics may potentiate the hypotension seen with aldesleukin, IL 2.
Alemtuzumab: (Moderate) Alemtuzumab may cause hypotension. Careful monitoring of blood pressure and hypotensive symptoms is recommended especially in patients with ischemic heart disease and in patients on antihypertensive agents.
Alendronate; Cholecalciferol: (Moderate) Dose adjustment of vitamin D or vitamin D analogs may be necessary during coadministration with thiazide diuretics. Additionally, serum calcium concentrations should be monitored frequently. Monitor more frequently in patients with a history of hypercalcemia. Hypercalcemia may be exacerbated by coadministration of vitamin D or vitamin D analogs and thiazide diuretics. Thiazide diuretics are known to induce hypercalcemia by reducing the excretion of calcium in the urine.
Alfentanil: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when a thiazide diuretic is administered with alfentanil. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Aliskiren: (Major) Aliskiren-containing products are contraindicated in combination with angiotensin-converting enzyme inhibitors (ACE inhibitors) in patients with diabetes mellitus. In general, avoid combined use of two renin-angiotensin-aldosterone system (RAAS) inhibitors, particularly in patients with CrCl less than 60 mL/minute. Combination therapy increases the risk for hyperkalemia, renal impairment, and other side effects. Most patients receiving a comination of two RAAS inhibitors, such as ACE inhibitors and aliskiren do not obtain any additional benefit compared to monotherapy. Closely monitor blood pressure, renal function, and electrolytes if aliskiren must be combined with another RAAS inhibitor. In the ALTITUDE trial, patients with type 2 diabetes and renal impairment, a population at high risk for cardiovascular and renal events, were given aliskiren in addition to ACE inhibitors or ARBs. The trial was stopped early because aliskiren was associated with an increased risk of non-fatal stroke, renal complications, hyperkalemia, and hypotension. In the Veterans Affairs Nephropathy in Diabetes (VA NEPHRON-D) trial, no additional benefit over monotherapy was seen in patients receiving the combination of losartan and lisinopril compared to monotherapy; however, there was an increased incidence of hyperkalemia and acute renal injury.
Aliskiren; Hydrochlorothiazide, HCTZ: (Major) Aliskiren-containing products are contraindicated in combination with angiotensin-converting enzyme inhibitors (ACE inhibitors) in patients with diabetes mellitus. In general, avoid combined use of two renin-angiotensin-aldosterone system (RAAS) inhibitors, particularly in patients with CrCl less than 60 mL/minute. Combination therapy increases the risk for hyperkalemia, renal impairment, and other side effects. Most patients receiving a comination of two RAAS inhibitors, such as ACE inhibitors and aliskiren do not obtain any additional benefit compared to monotherapy. Closely monitor blood pressure, renal function, and electrolytes if aliskiren must be combined with another RAAS inhibitor. In the ALTITUDE trial, patients with type 2 diabetes and renal impairment, a population at high risk for cardiovascular and renal events, were given aliskiren in addition to ACE inhibitors or ARBs. The trial was stopped early because aliskiren was associated with an increased risk of non-fatal stroke, renal complications, hyperkalemia, and hypotension. In the Veterans Affairs Nephropathy in Diabetes (VA NEPHRON-D) trial, no additional benefit over monotherapy was seen in patients receiving the combination of losartan and lisinopril compared to monotherapy; however, there was an increased incidence of hyperkalemia and acute renal injury.
Allopurinol: (Moderate) Monitor renal function and for signs and symptoms of hypersensitivity and skin rash during concomitant use of allopurinol and thiazide diuretics; reduce the allopurinol dose in persons with renal impairment and concomitant thiazide diuretic use. Concomitant use may increase the risk of severe skin rash and renal impairment may further increase the risk. Discontinue allopurinol at the first appearance of skin rash or other signs which may indicate a hypersensitivity when using these drugs concomitantly.
Alogliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Alogliptin; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Alogliptin; Pioglitazone: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Alpha-glucosidase Inhibitors: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Alprostadil: (Minor) The concomitant use of systemic alprostadil injection and antihypertensive agents, such as angiotensin-converting enzyme inhibitors (ACE inhibitors), may cause additive hypotension. Caution is advised with this combination. Systemic drug interactions with the urethral suppository (MUSE) or alprostadil intracavernous injection are unlikely in most patients because low or undetectable amounts of the drug are found in the peripheral venous circulation following administration. In those men with significant corpora cavernosa venous leakage, hypotension might be more likely. Use caution with in-clinic dosing for erectile dysfunction (ED) and monitor for the effects on blood pressure. However, in clinical trials with alprostadil intracavernous injection, anti-hypertensive agents had no apparent effect on the safety and efficacy of alprostadil. (Minor) The concomitant use of systemic alprostadil injection and antihypertensive agents, such as thiazide diuretics, may cause additive hypotension. Caution is advised with this combination. Systemic drug interactions with the urethral suppository (MUSE) or alprostadil intracavernous injection are unlikely in most patients because low or undetectable amounts of the drug are found in the peripheral venous circulation following administration. In those men with significant corpora cavernosa venous leakage, hypotension might be more likely. Use caution with in-clinic dosing for erectile dysfunction (ED) and monitor for the effects on blood pressure. In addition, the presence of medications in the circulation that attenuate erectile function may influence the response to alprostadil. However, in clinical trials with alprostadil intracavernous injection, anti-hypertensive agents had no apparent effect on the safety and efficacy of alprostadil.
Aluminum Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Carbonate: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Hydroxide; Simethicone: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Aluminum Hydroxide; Magnesium Trisilicate: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Amifostine: (Major) Patients receiving angiotensin-converting enzyme inhibitors should be closely monitored during amifostine infusions due to additive effects. Patients receiving amifostine at doses recommended for chemotherapy should have antihypertensive therapy interrupted 24 hours preceding administration of amifostine. If the antihypertensive cannot be stopped, patients should not receive amifostine. (Major) Patients receiving antihypertensive agents should be closely monitored during amifostine infusions due to additive effects. If possible, patients should not take their antihypertensive medication 24 hours before receiving amifostine. Patients who can not stop their antihypertensive agents should not receive amifostine or be closely monitored during the infusion and, possibly, given lower doses.
Amiloride: (Major) Amiloride should be used very cautiously with agents that have potential to induce hyperkalemia; serum potassium levels monitored when such agents are coadministered with amiloride. Simultaneous use of a potassium-sparing diuretic (e.g., amiloride) with angiotensin-converting enzyme inhibitors (ACE inhibitors) can increase the risk of hyperkalemia, especially in the presence of renal impairment (renal disease, elderly patients). These agents should be used with caution and serum potassium levels monitored when the substances are coadministered. The Beers Criteria recommends avoiding routine use of this combination in older adults; reserve this combination for patients with demonstrated hypokalemia while taking an ACE inhibitor.
Amiloride; Hydrochlorothiazide, HCTZ: (Major) Amiloride should be used very cautiously with agents that have potential to induce hyperkalemia; serum potassium levels monitored when such agents are coadministered with amiloride. Simultaneous use of a potassium-sparing diuretic (e.g., amiloride) with angiotensin-converting enzyme inhibitors (ACE inhibitors) can increase the risk of hyperkalemia, especially in the presence of renal impairment (renal disease, elderly patients). These agents should be used with caution and serum potassium levels monitored when the substances are coadministered. The Beers Criteria recommends avoiding routine use of this combination in older adults; reserve this combination for patients with demonstrated hypokalemia while taking an ACE inhibitor.
Aminolevulinic Acid: (Moderate) Thiazide diuretics may cause photosensitivity and may increase the photosensitization effects of photosensitizing agents used in photodynamic therapy. Prevention of photosensitivity includes adequate protection from sources of UV radiation (e.g., avoiding sun exposure and tanning booths) and the use of protective clothing and sunscreens on exposed skin.
Amlodipine; Benazepril: (Major) Discontinue the thiazide diuretic prior to starting benazepril, if possible, or start benazepril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Amlodipine; Celecoxib: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Amlodipine; Olmesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Amlodipine; Valsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Amobarbital: (Moderate) Concurrent use of amobarbital with antihypertensive agents may lead to hypotension. Monitor for decreases in blood pressure during times of coadministration.
Amoxicillin; Clarithromycin; Omeprazole: (Moderate) Monitor magnesium concentration before and periodically during concomitant omeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Amphetamine; Dextroamphetamine Salts: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised. (Minor) Amphetamines may counteract the activity of some antihypertensive agents, such as thiazide diuretics. Close monitoring of blood pressure is advised. Thiazide diuretics may also increase and prolong the actions of amphetamines by increasing the urinary pH.
Amphotericin B lipid complex (ABLC): (Moderate) The risk of developing severe hypokalemia can be increased when amphotericin B is coadministered with thiazide diuretics. Monitoring serum potassium levels and cardiac function is advised, and potassium supplementation may be required.
Amphotericin B liposomal (LAmB): (Moderate) The risk of developing severe hypokalemia can be increased when amphotericin B is coadministered with thiazide diuretics. Monitoring serum potassium levels and cardiac function is advised, and potassium supplementation may be required.
Amphotericin B: (Moderate) The risk of developing severe hypokalemia can be increased when amphotericin B is coadministered with thiazide diuretics. Monitoring serum potassium levels and cardiac function is advised, and potassium supplementation may be required.
Angiotensin II receptor antagonists: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Angiotensin II: (Moderate) Angiotensin converting enzyme inhibitors (ACE inhibitors) may increase the response to angiotensin II. Angiotensin II is a naturally occurring peptide hormone of the renin-angiotensin-aldosterone system (RAAS) that causes vasoconstriction and an increase in blood pressure. ACE inhibitors reduce the breakdown of angiotensin II.
Antacids: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Anticholinergics: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Apomorphine: (Moderate) Use of angiotensin-converting enzyme inhibitors (ACE inhibitors) and apomorphine together can increase the hypotensive effects of apomorphine. Monitor blood pressure regularly during use of this combination. (Moderate) Use of thiazide diuretics and apomorphine together can increase the hypotensive effects of apomorphine. Monitor blood pressure regularly during use of this combination.
Apraclonidine: (Minor) Alpha blockers as a class may reduce heart rate and blood pressure. While no specific drug interactions have been identified with systemic agents and apraclonidine during clinical trials, it is theoretically possible that additive blood pressure reductions could occur when apraclonidine is combined with the use of antihypertensive agents. Patients using cardiovascular drugs concomitantly with apraclonidine should have their pulse and blood pressure monitored periodically.
Aprotinin: (Moderate) The manufacturer recommends using aprotinin cautiously in patients that are receiving drugs that can affect renal function, such as ACE inhibitors, as the risk of renal impairment may be increased.
Arformoterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Aripiprazole: (Minor) Aripiprazole may enhance the hypotensive effects of antihypertensive agents.
Arsenic Trioxide: (Moderate) Concomitant use of thiazide diuretics and arsenic trioxide should be done cautiously. Electrolyte abnormalities, such as hypokalemia and hypomagnesemia, may increase the risk for QT prolongation and torsade de pointes.
Articaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine. (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and thiazide diuretic use. Thiazide diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Asenapine: (Moderate) Secondary to alpha-blockade, asenapine can produce vasodilation that may result in additive effects during concurrent use of antihypertensive agents. The potential reduction in blood pressure can precipitate orthostatic hypotension and associated dizziness, tachycardia, and syncope. If concurrent use of asenapine and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Aspirin, ASA; Omeprazole: (Moderate) Monitor magnesium concentration before and periodically during concomitant omeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Aspirin, ASA; Oxycodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and oxycodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Atracurium: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Atropine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Atropine; Difenoxin: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Azathioprine: (Major) The use of ACE inhibitors in hypertensive patients receiving azathioprine has been reported to induce anemia and severe leukopenia. This combination should be avoided where possible. When concurrent azathioprine and ACE inhibitor therapy is necessary, the patient should be monitored cautiously for potential myelosuppression.
Azilsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Azilsartan; Chlorthalidone: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Baclofen: (Moderate) Baclofen has been associated with hypotension. Concurrent use with baclofen and antihypertensive agents may result in additive hypotension. Dosage adjustments of the antihypertensive medication may be required.
Barbiturates: (Moderate) Barbiturates may potentiate orthostatic hypotension when used concurrently with thiazide diuretics.
Belladonna; Opium: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with opium. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone. (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Benazepril: (Major) Discontinue the thiazide diuretic prior to starting benazepril, if possible, or start benazepril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Benazepril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting benazepril, if possible, or start benazepril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Benzhydrocodone; Acetaminophen: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with benzhydrocodone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: (Moderate) Thiazide diuretics may cause the urine to become alkaline. This may reduce the effectiveness of methenamine by inhibiting its conversion to formaldehyde. (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Benzphetamine: (Minor) Amphetamines may counteract the activity of some antihypertensive agents, such as thiazide diuretics. Close monitoring of blood pressure is advised. Thiazide diuretics may also increase and prolong the actions of amphetamines by increasing the urinary pH. (Minor) Benzphetamine may increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Benztropine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Beta-agonists: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Bortezomib: (Moderate) Patients on antihypertensive agents receiving bortezomib treatment may require close monitoring of their blood pressure and dosage adjustment of their medication. During clinical trials of bortezomib, hypotension was reported in roughly 12 percent of patients.
Brexpiprazole: (Moderate) Due to brexpiprazole's antagonism at alpha 1-adrenergic receptors, the drug may enhance the hypotensive effects of alpha-blockers and other antihypertensive agents.
Brompheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Brompheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Brompheniramine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Brompheniramine; Pseudoephedrine; Dextromethorphan: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Budesonide; Formoterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Budesonide; Glycopyrrolate; Formoterol: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms. (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Bupivacaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine. (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and thiazide diuretic use. Thiazide diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Bupivacaine; Meloxicam: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Buprenorphine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and buprenorphine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Buprenorphine; Naloxone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and buprenorphine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Cabergoline: (Moderate) Cabergoline should be used cautiously with antihypertensive agents, including angiotensin-converting enzyme inhibitors. Cabergoline has been associated with hypotension. Initial doses of cabergoline higher than 1 mg may produce orthostatic hypotension. It may be advisable to monitor blood pressure. (Moderate) Cabergoline should be used cautiously with antihypertensive agents, including thiazide diuretics. Cabergoline has been associated with hypotension. Initial doses of cabergoline higher than 1 mg may produce orthostatic hypotension. It may be advisable to monitor blood pressure.
Calcium Carbonate: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Famotidine; Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Magnesium Hydroxide; Simethicone: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Carbonate; Simethicone: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Calcium Phosphate, Supersaturated: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as angiotensin-converting enzyme inhibitors, may increase the risk of acute phosphate nephropathy in patients taking sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous. (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as diuretics, may increase the risk of acute phosphate nephropathy in patients taking sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous.
Calcium: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Calcium; Vitamin D: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously. (Moderate) Dose adjustment of vitamin D or vitamin D analogs may be necessary during coadministration with thiazide diuretics. Additionally, serum calcium concentrations should be monitored frequently. Monitor more frequently in patients with a history of hypercalcemia. Hypercalcemia may be exacerbated by coadministration of vitamin D or vitamin D analogs and thiazide diuretics. Thiazide diuretics are known to induce hypercalcemia by reducing the excretion of calcium in the urine.
Canagliflozin: (Major) Assess and correct volume status before initiating canagliflozin in persons receiving concomitant thiazide diuretics. Monitor for signs and symptoms of volume depletion and loss of glycemic control after initiating therapy due to increased risk for volume depletion or hypotension and loss of blood glucose control. Persons receiving thiazide diuretics may be at increased risk for volume depletion or hypotension with concomitant canagliflozin therapy. Thiazide diuretics tend to produce hyperglycemia and may lead to loss of glycemic control.
Canagliflozin; Metformin: (Major) Assess and correct volume status before initiating canagliflozin in persons receiving concomitant thiazide diuretics. Monitor for signs and symptoms of volume depletion and loss of glycemic control after initiating therapy due to increased risk for volume depletion or hypotension and loss of blood glucose control. Persons receiving thiazide diuretics may be at increased risk for volume depletion or hypotension with concomitant canagliflozin therapy. Thiazide diuretics tend to produce hyperglycemia and may lead to loss of glycemic control. (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Candesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Candesartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Captopril: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Carbamazepine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant use of carbamazepine and thiazide diuretics due to additive risk of developing hyponatremia.
Carbidopa; Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects. (Moderate) Monitor blood pressure during concomitant levodopa and thiazide diuretic use due to risk for additive hypotension; a thiazide diuretic dosage adjustment may be necessary. Symptomatic postural hypotension has occurred when carbidopa; levodopa was added in a person receiving antihypertensive drugs.
Carbidopa; Levodopa; Entacapone: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects. (Moderate) Monitor blood pressure during concomitant levodopa and thiazide diuretic use due to risk for additive hypotension; a thiazide diuretic dosage adjustment may be necessary. Symptomatic postural hypotension has occurred when carbidopa; levodopa was added in a person receiving antihypertensive drugs.
Cardiac glycosides: (Moderate) Monitor serum magnesium and potassium during concomitant cardiac glycoside and thiazide diuretic use. Potassium-depleting diuretics are a major contributing factor to digoxin toxicity.
Cariprazine: (Moderate) Orthostatic vital signs should be monitored in patients who are at risk for hypotension, such as those receiving cariprazine in combination with antihypertensive agents. Atypical antipsychotics may cause orthostatic hypotension and syncope, most commonly during treatment initiation and dosage increases. Patients should be informed about measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning, or rising slowly from a seated position. Consider a cariprazine dose reduction if hypotension occurs.
Celecoxib: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Celecoxib; Tramadol: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and tramadol; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Cetirizine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlordiazepoxide; Clidinium: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Chloroprocaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Chlorpheniramine; Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine:<

/strong> (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) Opiate agonists may potentiate orthostatic hypotension when used concurrently with thiazide diuretics. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Chlorpheniramine; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlorpheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Chlorpheniramine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chlorpropamide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Cholestyramine: (Moderate) Cholestyramine, an ion exchange resin, binds hydrochlorothiazide and reduces its absorption from the gastrointestinal tract by up to 85% when co-administered as single doses. Although the manufacturer for Questran recommends that other medicines be taken at least 1 hour before or 4-6 hours after cholestyramine, it has been recommended that thiazides be administered at least 4 hours before or after cholestyramine to minimize the reduction in absorption. By administering hydrochlorothiazide at least 4 hours before cholestyramine, the decrease in absorption of hydrochlorothiazide is approximately 30-35%.
Cidofovir: (Contraindicated) The administration of cidofovir with another potentially nephrotoxic agent, such as diuretics, is contraindicated. Diuretics should be discontinued at least 7 days prior to beginning cidofovir.
Cisapride: (Major) Cisapride should be used with great caution in patients receiving thiazide diuretics. Drugs that are associated with depletion of electrolytes may cause cisapride-induced cardiac arrhythmias. Serum electrolytes and creatinine should be assessed prior to administration of cisapride and whenever conditions develop that may affect electrolyte imbalance or renal function.
Cisatracurium: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Citalopram: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and citalopram use; consider discontinuing citalopram if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Clindamycin; Tretinoin: (Moderate) A manufacturer of topical tretinoin states that tretinoin, ATRA should be administered with caution in patients who are also taking drugs known to be photosensitizers, such as thiazide diuretics, as concomitant use may augment phototoxicity. Patients should take care and use proper techniques to limit sunlight and UV exposure of treated areas.
Clozapine: (Moderate) Caution is advisable during concurrent use of clozapine and thiazide diuretics as concurrent use may increase the risk and severity of hypotension. In addition, electrolyte imbalance caused by thiazide diuretics may increase the risk of QT prolongation by clozapine. (Moderate) Lisinopril may decrease the renal elimination of clozapine and metabolites. Clozapine toxicity, including irritability, anger, insomnia, nightmares and sialorrhea may occur. The mechanism of this interaction is unclear; however, as lisinopril does not undergo metabolism, cytochrome P450 enzyme involvement is unlikely. It is speculated that a decrease in renal elimination of clozapine occurs due to a lisinopril-induced reduction in glomerular filtration rate (GFR). Plasma clozapine concentrations should be measured carefully during concomitant lisinopril therapy; another antihypertensive class may need to be selected. In addition, clozapine used concomitantly with the antihypertensive agents can increase the risk and severity of hypotension by potentiating the effect of the antihypertensive drug.
Cocaine: (Major) Use of cocaine with antihypertensive agents may increase the antihypertensive effects of the antihypertensive medications or may potentiate cocaine-induced sympathetic stimulation.
Codeine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Codeine; Guaifenesin: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic. (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Codeine; Phenylephrine; Promethazine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Codeine; Promethazine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and codeine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Co-Enzyme Q10, Ubiquinone: (Moderate) Co-enzyme Q10, ubiquinone (CoQ10) may lower blood pressure. CoQ10 use in combination with antihypertensive agents may lead to additional reductions in blood pressure in some individuals. Patients who choose to take CoQ10 concurrently with antihypertensive medications should receive periodic blood pressure monitoring. Patients should be advised to inform their prescriber of their use of CoQ10. (Moderate) Monitor blood pressure during concomitant co-enzyme Q10 (ubiquinone) and thiazide diuretic use. Concomitant use may result in additive hypotension.
Colestipol: (Moderate) Although to a lesser extent than cholestyramine, colestipol also has been shown to inhibit the GI absorption and therapeutic response of thiazide diuretics. Single doses of colestipol resins reduce the absorption of HCTZ by up to 43%. Administering thiazide diuretics at least 2 hours before colestipol has been suggested to minimize the interaction.
Corticosteroids: (Moderate) Monitor potassium concentrations during concomitant corticosteroid and thiazide diuretic use due to risk for additive hypokalemia; potassium supplementation may be necessary. Both corticosteroids and thiazide diuretics cause increased renal potassium loss.
Corticotropin, ACTH: (Minor) Monitor potassium concentrations during concomitant corticotropin and thiazide diuretic use due to risk for additive hypokalemia; potassium supplementation may be necessary. Both corticotropin and thiazide diuretics cause increased renal potassium loss.
Cosyntropin: (Moderate) Use cosyntropin cautiously in patients receiving diuretics. Cosyntropin may accentuate the electrolyte loss associated with diuretic therapy.
Cyclophosphamide: (Moderate) Closely monitor complete blood counts if coadministration of cyclophosphamide with angiotensin-converting enzyme inhibitors (ACE inhibitors) is necessary as there is an increased risk of hematologic toxicity (specifically leukopenia) and immunosuppression. (Moderate) Closely monitor complete blood counts if coadministration of cyclophosphamide with thiazide diuretics is necessary as there is an increased risk of hematologic toxicity and immunosuppression.
Cyclosporine: (Moderate) Several cases of acute renal failure have been associated with the addition of angiotensin-converting enzyme (ACE) inhibitors to cyclosporine therapy in renal transplant patients. In response to cyclosporine-induced renal afferent vasoconstriction and glomerular hypoperfusion, angiotensin II is required to maintain an adequate glomerular filtration rate. Inhibition of ACE could reduce renal function acutely. Also, cyclosporine can cause hyperkalemia, and inhibition of angiotensin II leads to reduced aldosterone concentrations, which can increase the serum potassium concentration. Closely monitor renal function and serum potassium concentrations in patients receiving cyclosporine concurrently with ACE inhibitors or potassium salts.
Dapagliflozin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Dapagliflozin; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Dapagliflozin; Saxagliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Desloratadine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Desmopressin: (Moderate) Monitor serum sodium more frequently during concomitant desmopressin and thiazide diuretic use due to increased risk of water intoxication with hyponatremia.
Desvenlafaxine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Dexbrompheniramine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dexlansoprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with thiazide diuretics (chlorothiazide, hydrochlorothiazide, indapamide, and metolazone). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dextromethorphan; Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
Diazoxide: (Moderate) Additive hypotensive effects can occur with the concomitant administration of diazoxide with other antihypertensive agents. This interaction can be therapeutically advantageous, but dosages must be adjusted accordingly. The manufacturer advises that IV diazoxide should not be administered to patients within 6 hours of receiving other antihypertensive agents. (Moderate) Enhanced hyperglycemia is possible during concurrent use of diazoxide and thiazide diuretics. Additive hypotensive effects can also occur with the concomitant administration of diazoxide with thiazide diuretics.
Dichlorphenamide: (Moderate) Use dichlorphenamide and diuretics together with caution. Dichlorphenamide increases potassium excretion and can cause hypokalemia and should be used cautiously with other drugs that may cause hypokalemia including loop diuretics and thiazide diuretics. Measure potassium concentrations at baseline and periodically during dichlorphenamide treatment. If hypokalemia occurs or persists, consider reducing the dose or discontinuing dichlorphenamide therapy.
Diclofenac: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diclofenac; Misoprostol: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Dicyclomine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Diethylpropion: (Major) Diethylpropion has vasopressor effects and may limit the benefit of angiotensin-converting enzyme inhibitors. Although leading drug interaction texts differ in the potential for an interaction between diethylpropion and this group of antihypertensive agents, these effects are likely to be clinically significant and have been described in hypertensive patients on these medications. (Major) Diethylpropion has vasopressor effects and may limit the benefit of thiazide diuretics. Although leading drug interaction texts differ in the potential for an interaction between diethylpropion and this group of antihypertensive agents, these effects are likely to be clinically significant and have been described in hypertensive patients on these medications.
Diflunisal: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Digoxin: (Major) Coadministration of digoxin and captopril increases the serum concentration and AUC of digoxin by 58% and 39%, respectively. However, captopril and digoxin are administered together in patients with congestive heart failure. Measure serum digoxin concentrations before initiating captopril. Reduce digoxin concentrations by decreasing the digoxin dose by approximately 30-50% or by modifying the dosing frequency and continue monitoring. In addition, caution should be exercised when administering digoxin with drugs that may cause a significant deterioration in renal function including angiotensin-converting enzyme inhibitors (ACE inhibitors). A decline in glomerular filtration or tubular secretion may impair the excretion of digoxin. Close monitoring of serum digoxin concentrations is essential to avoid enhanced toxicity. (Moderate) Monitor serum magnesium and potassium during concomitant cardiac glycoside and thiazide diuretic use. Potassium-depleting diuretics are a major contributing factor to digoxin toxicity.
Diphenhydramine; Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diphenhydramine; Naproxen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Diphenoxylate; Atropine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Dobutamine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives such as metolazone when administered concomitantly.
Dofetilide: (Contraindicated) Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics and thiazide diuretics, increasing the potential for dofetilide-induced torsade de pointes. Additionally, in patients treated with either hydrochlorothiazide 50 mg or hydrochlorothiazide/triamterene 50 mg/100 mg daily in combination with dofetilide 500 mcg twice daily for 5 days, dofetilide AUC and Cmax concentrations increased by 27% and 21%, respectively, for the hydrochlorothiazide alone group and by 30% and 16%, respectively, for the hydrochlorothiazide/triamterene group. Furthermore, a 197% and 190% QTc increase over time was seen in the hydrochlorothiazide and hydrochlorothiazide/triamterene groups, respectively. Based on these findings, the manufacturer of dofetilide contraindicates the concomitant use of hydrochlorothiazide (alone or in combination with other drugs such as triamterene); these findings can be explained both by an increase in the plasma concentration of dofetilide and a reduction in the serum potassium concentration. In a population pharmacokinetic analysis of plasma dofetilide concentrations, the mean dofetilide clearance of dofetilide was 16% lower in patients on thiazide diuretics. It is prudent to avoid the use of any thiazide diuretic in combination with dofetilide.
Dolasetron: (Moderate) Caution is advisable during concurrent use of dolasetron and thiazide diuretics as electrolyte imbalance caused by diuretics may increase the risk of QT prolongation with dolasetron.
Donepezil; Memantine: (Minor) Memantine reduced the bioavailability of hydrochlorothiazide by roughly 20% in a drug interaction study. The clinical significance of this pharmacokinetic interaction, if any, is unknown.
Dopamine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives such as metolazone when administered concomitantly.
Droperidol: (Moderate) Caution is advised when using droperidol in combination with thiazide diuretics which may lead to electrolyte abnormalities, especially hypokalemia or hypomagnesemia, as such abnormalities may increase the risk for QT prolongation or cardiac arrhythmias.
Drospirenone: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Estetrol: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Estradiol: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Ethinyl Estradiol: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Drospirenone; Ethinyl Estradiol; Levomefolate: (Moderate) Drospirenone has antimineralocorticoid effects and may increase serum potassium. The concurrent use of ACE inhibitors may increase the risk of hyperkalemia, especially in the presence of renal impairment. Monitor serum potassium during the 1st month of drospirenone treatment if an Angiotensin-Converting Enzyme inhibitor (ACE inhibitor) is used concurrently and thereafter as clinically indicated. Also monitor for any changes in blood pressure, fluid retention, or renal function.
Dulaglutide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Duloxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia. (Moderate) Orthostatic hypotension and syncope have been reported during duloxetine administration. The concurrent administration of antihypertensive agents and duloxetine may increase the risk of hypotension. Monitor blood pressure if the combination is necessary.
Empagliflozin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Empagliflozin; Linagliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Empagliflozin; Linagliptin; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Empagliflozin; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Enalapril, Enalaprilat: (Major) Discontinue the thiazide diuretic prior to starting enalapril, if possible, or start enalapril at the lower dose of 2.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Enalapril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting enalapril, if possible, or start enalapril at the lower dose of 2.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Entecavir: (Moderate) Because entecavir is primarily eliminated by the kidneys and ACE inhibitors can affect renal function, concurrent administration with ACE inhibitors may increase the serum concentrations of entecavir and adverse events. Monitor for adverse effects when these drugs are coadministered.
Ephedrine: (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved. (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by thiazide diuretics. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved.
Ephedrine; Guaifenesin: (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved. (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by thiazide diuretics. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved.
Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine. (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and thiazide diuretic use. Thiazide diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Eplerenone: (Major) Monitor serum potassium and serum creatinine concentrations within 3 to 7 days of initiating coadministration of eplerenone and angiotensin-converting enzyme (ACE) inhibitors. Hyperkalemia risk is increased when eplerenone is used with ACE inhibitors. Patients who develop hyperkalemia may continue eplerenone with proper dose adjustment; eplerenone dose reduction decreases potassium concentrations.
Eprosartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Eprosartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Ertugliflozin; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Ertugliflozin; Sitagliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Escitalopram: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and escitalopram use; consider discontinuing escitalopram if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Esomeprazole: (Moderate) Monitor magnesium concentration before and periodically during concomitant esomeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Estradiol: (Minor) Estrogens can induce fluid retention and may increase blood pressure in some patients; patients who are receiving antihypertensive agents concurrently with hormonal contraceptives should be monitored for antihypertensive effectiveness. (Minor) Estrogens can induce fluid retention and may increase blood pressure in some patients; patients who are receiving antihypertensive agents concurrently with hormone therapy should be monitored for antihypertensive effectiveness.
Ethanol: (Major) Advise patients to avoid alcohol while taking thiazide diuretics. Ingesting alcohol can increase the risk for orthostatic hypotension when taking a thiazide diuretic.
Ethiodized Oil: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Etodolac: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Etomidate: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents. (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Everolimus: (Major) Avoid coadministration of everolimus with angiotensin-converting enzyme inhibitors (ACE inhibitors) as the risk of angioedema, with or without respiratory impairment, may be increased. In a pooled analysis of randomized, double-blind oncology clinical trials, angioedema was reported in 6.8% of patients receiving concomitant everolimus and ACE inhibitor therapy, compared to 1.3% of patients with an ACE inhibitor alone.
Exenatide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Fenoprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Fentanyl: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and fentanyl; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Fexofenadine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Finerenone: (Moderate) Monitor serum potassium concentrations closely if finerenone and angiotensin-converting enzyme inhibitors (ACEI) are used together. Concomitant use may increase the risk of hyperkalemia.
Fish Oil, Omega-3 Fatty Acids (Dietary Supplements): (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents. (Moderate) Monitor blood pressure during concomitant fish oil and thiazide diuretic use. Concomitant use may result in additive hypotension; high doses of fish oil may produce a blood pressure lowering effect.
Flavoxate: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Fluconazole: (Moderate) Monitor for fluconazole-related adverse events during concomitant hydrochlorothiazide use. Hydrochlorothiazide may decrease the renal clearance of fluconazole. Coadministration of fluconazole 100 mg PO and hydrochlorothiazide 50 mg PO for 10 days in normal volunteers (n = 13) resulted in a significant increase in fluconazole AUC and Cmax compared to fluconazole given alone. There was a mean +/- SD increase in fluconazole AUC and Cmax of 45% +/- 31% and 43% +/- 31%, respectively. These changes are attributed to a mean +/- SD reduction in fluconazole renal clearance of 30% +/- 12%.
Fluocinolone; Hydroquinone; Tretinoin: (Moderate) A manufacturer of topical tretinoin states that tretinoin, ATRA should be administered with caution in patients who are also taking drugs known to be photosensitizers, such as thiazide diuretics, as concomitant use may augment phototoxicity. Patients should take care and use proper techniques to limit sunlight and UV exposure of treated areas.
Fluorescein: (Moderate) Patients on angiotensin-converting enzyme inhibitors are at an increased risk of adverse reactions when administered fluorescein injection. If fluorescein injection is deemed necessary in a patient on ACE inhibitor therapy, monitor as appropriate during and after the procedure.
Fluoxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and fluoxetine use; consider discontinuing fluoxetine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Flurbiprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Fluticasone; Salmeterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Fluticasone; Umeclidinium; Vilanterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Fluticasone; Vilanterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Fluvoxamine: (Moderate) Patients receiving a diuretic during treatment with fluvoxamine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/L have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of fluvoxamine should be considered in patients who develop symptomatic hyponatremia.
Formoterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Formoterol; Mometasone: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Fosinopril: (Major) Discontinue the thiazide diuretic prior to starting fosinopril, if possible, or start fosinopril at a lower dose to minimize hypotension. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Fosinopril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting fosinopril, if possible, or start fosinopril at a lower dose to minimize hypotension. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
General anesthetics: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents. (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Glimepiride: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Glipizide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Glipizide; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke an d cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Glyburide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Glyburide; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Glycopyrrolate: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Glycopyrrolate; Formoterol: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms. (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Gold: (Minor) Nitritoid reactions (facial flushing, diaphoresis, dizziness, nausea/vomiting, hypotension, tachycardia, syncope, and anaphylactic type reactions) or vasomotor reactions have been reported rarely in patients receiving injectable gold and concomitant ACE inhibitor therapy. Monitor closely for nitritoid reactions during co-therapy with gold and ACE inhibitor agents.
Granisetron: (Moderate) According to the manufacturer, caution is warranted when administering granisetron to patients with preexisting electrolyte abnormalities. Patients taking certain diuretics may develop an electrolyte abnormality that may lead to cardiac dysrhythmias and/or QT prolongation. Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics and thiazide diuretics, increasing the potential for cardiac arrhythmias.
Guaifenesin; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Guaifenesin; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Halobetasol; Tazarotene: (Moderate) The manufacturer states that tazarotene should be administered with caution in patients who are also taking drugs known to be photosensitizers, such as thiazide diuretics, as concomitant use may augment phototoxicity. Patients should take care and use proper techniques to limit sunlight and UV exposure of treated areas.
Haloperidol: (Moderate) Caution is advisable during concurrent use of haloperidol and thiazide diuretics as electrolyte imbalance caused by diuretics may increase the risk of QT prolongation with haloperidol. Concomitant use may also cause additive hypotension. (Moderate) In general, haloperidol should be used cautiously with antihypertensive agents due to the possibility of additive hypotension.
Homatropine; Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic. (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and nitrate use due to risk for additive hypotension.
Hydrochlorothiazide, HCTZ; Moexipril: (Major) Discontinue the thiazide diuretic prior to starting moexipril, if possible, or start moexipril at the lower dose of 3.75 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Hydrocodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Hydrocodone; Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Hydrocodone; Pseudoephedrine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and hydrocodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic. (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Hydromorphone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with hydromorphone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Hyoscyamine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate; Sodium Biphosphate: (Moderate) Thiazide diuretics may cause the urine to become alkaline. This may reduce the effectiveness of methenamine by inhibiting its conversion to formaldehyde. (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Ibritumomab Tiuxetan: (Major) Avoid coadministration of potassium phosphate and angiotensin-converting enzyme inhibitors as concurrent use may increase the risk of severe and potentially fatal hyperkalemia, particularly in high-risk patients (renal impairment, cardiac disease, adrenal insufficiency). If concomitant use is necessary, closely monitor serum potassium concentrations.
Ibuprofen lysine: (Moderate) Ibuprofen lysine may reduce the effect of diuretics; diuretics can increase the risk of nephrotoxicity of NSAIDs in dehydrated patients. During coadministration of NSAIDs and diuretic therapy, patients should be monitored for changes in the effectiveness of their diuretic therapy and for signs and symptoms of renal impairment.
Ibuprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Ibuprofen; Famotidine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Ibuprofen; Oxycodone: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and oxycodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Ibuprofen; Pseudoephedrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Icatibant: (Minor) Although clinical data are lacking, icatibant is a bradykinin B2 receptor antagonist and may theoretically potentiate the antihypertensive effect of ACE inhibitors.
Icosapent ethyl: (Moderate) Thiazide diuretics may exacerbate hypertriglyceridemia and should be discontinued or changed to alternate therapy, if possible, prior to initiation of icosapent ethyl.
Iloperidone: (Moderate) Secondary to alpha-blockade, iloperidone can produce vasodilation that may result in additive effects during concurrent use with antihypertensive agents. The potential reduction in blood pressure can precipitate orthostatic hypotension and associated dizziness, tachycardia, and syncope. If concurrent use of iloperidone and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
Iloprost: (Moderate) Further reductions in blood pressure may occur when inhaled iloprost is administered to patients receiving other antihypertensive agents.
Incretin Mimetics: (Moderate) Monitor blood glucose during concomitant incretin mimetic and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Indacaterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Indacaterol; Glycopyrrolate: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms. (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Indapamide: (Moderate) The effects of indapamide may be additive when administered with other antihypertensive agents or diuretics. In some patients, this may be desirable, but orthostatic hypotension may occur. Patients with hyponatremia or hypovolemia are more susceptible to developing reversible renal insufficiency when given an angiotensin-converting enzyme inhibitors (ACE Inhibitors) and diuretic therapy concomitantly.
Indomethacin: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Inotersen: (Moderate) Use caution with concomitant use of inotersen and diuretics due to the risk of glomerulonephritis and nephrotoxicity.
Insulin Degludec; Liraglutide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Insulin Glargine; Lixisenatide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Insulins: (Moderate) Monitor blood glucose during concomitant insulin and angiotensin-converting enzyme (ACE) inhibitor use; an insulin dose adjustment may be necessary. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor patients receiving insulin closely for changes in diabetic control when thiazide diuretics are instituted or discontinued; dosage adjustments may be required. Thiazide diuretics can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes.
Intravenous Lipid Emulsions: (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents. (Moderate) Monitor blood pressure during concomitant fish oil and thiazide diuretic use. Concomitant use may result in additive hypotension; high doses of fish oil may produce a blood pressure lowering effect.
Iodixanol: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Iohexol: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Iomeprol: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Iopamidol: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Iopromide: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Ioversol: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Ipratropium; Albuterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Irbesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Irbesartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Iron Dextran: (Moderate) The concomitant use of angiotensin-converting enzyme inhibitors (ACE inhibitors) with iron dextran may increase the risk for anaphylactic-type reactions. The factors that affect the risk for anaphylactic-type reactions to iron dextran products are not fully known but limited clinical data suggest the risk may be increased among patients with a history of drug allergy or multiple drug allergies. Patients should be monitored for signs and symptoms of anaphylactic-type reactions during all iron dextran administrations.
Isocarboxazid: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with angiotensin-converting enzyme inhibitors (ACE inhibitors). Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider. (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with diuretics. Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
Isoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents. (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Isoproterenol: (Moderate) The pharmacologic effects of isoproterenol may cause an increase in blood pressure. If isoproterenol is used concomitantly with antihypertensives, the blood pressure should be monitored as the administration of isoproterenol can compromise the effectiveness of antihypertensive agents.
Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and nitrate use due to risk for additive hypotension.
Isosorbide Mononitrate: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and nitrate use due to risk for additive hypotension.
Isosulfan Blue: (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Ketamine: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents. (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Ketoprofen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Ketorolac: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Lansoprazole: (Moderate) Monitor magnesium concentration before and periodically during concomitant lansoprazole and thiazide diuretic use due to risk for hypomagnesemia.
Lansoprazole; Amoxicillin; Clarithromycin: (Moderate) Monitor magnesium concentration before and periodically during concomitant lansoprazole and thiazide diuretic use due to risk for hypomagnesemia.
Lanthanum Carbonate: (Moderate) ACE Inhibitors should not be taken within 2 hours of dosing with lanthanum carbonate. Oral compounds known to interact with cationic antacids may similarly be bound with lanthanum carbonate and have their absorption reduced. If these agents are used concomitantly, separate the dosing intervals appropriately. Monitor the clinical condition of the patient to ensure the proper clinical response to the ACE inhibitor is obtained.
Lesinurad; Allopurinol: (Moderate) Monitor renal function and for signs and symptoms of hypersensitivity and skin rash during concomitant use of allopurinol and thiazide diuretics; reduce the allopurinol dose in persons with renal impairment and concomitant thiazide diuretic use. Concomitant use may increase the risk of severe skin rash and renal impairment may further increase the risk. Discontinue allopurinol at the first appearance of skin rash or other signs which may indicate a hypersensitivity when using these drugs concomitantly.
Levalbuterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects. (Moderate) Monitor blood pressure during concomitant levodopa and thiazide diuretic use due to risk for additive hypotension; a thiazide diuretic dosage adjustment may be necessary. Symptomatic postural hypotension has occurred when carbidopa; levodopa was added in a person receiving antihypertensive drugs.
Levomilnacipran: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Levorphanol: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with levorphanol. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Lidocaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine. (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and thiazide diuretic use. Thiazide diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Linagliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Linagliptin; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Liraglutide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Lisdexamfetamine: (Minor) Amphetamines may counteract the activity of some antihypertensive agents, such as thiazide diuretics. Close monitoring of blood pressure is advised. Thiazide diuretics may also increase and prolong the actions of amphetamines by increasing the urinary pH. (Minor) Lisdexamfetamine may increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised.
Lisinopril: (Major) Discontinue the thiazide diuretic prior to starting lisinopril, if possible, or start lisinopril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Lisinopril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting lisinopril, if possible, or start lisinopril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Lithium: (Moderate) Monitor lithium concentrations during concomitant use with thiazide diuretics; consider lower lithium starting doses and titrating slowly while frequently monitoring lithium concentrations and for signs of lithium toxicity. Thiazide diuretics reduce the renal clearance of lithium and increase the risk for lithium toxicity. (Moderate) Monitor serum lithium concentrations during concomitant angiotensin-converting enzyme inhibitor use; reduce the lithium dose based on serum lithium concentration and clinical response. Concomitant use may increase steady-state lithium concentrations.
Lixisenatide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Loop diuretics: (Major) Discontinue the loop diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure and renal function during concomitant use, particularly when doses are increased. Concomitant use may increase the risk for hypotension or renal failure. (Moderate) Monitor blood pressure, renal function, and serum electrolytes during concomitant loop diuretic and thiazide diuretic use; dosage adjustments may be necessary. Concomitant use may result in additive hypotension and fluid and/or electrolyte loss.
Loratadine; Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Losartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Losartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Lurasidone: (Moderate) Due to the antagonism of lurasidone at alpha-1 adrenergic receptors, the drug may enhance the hypotensive effects of alpha-blockers and other antihypertensive agents. If concurrent use of lurasidone and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
Magnesium Hydroxide: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Magnesium Salts: (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as angiotensin-converting enzyme inhibitors (ACE inhibitors).
Magnesium Sulfate; Potassium Sulfate; Sodium Sulfate: (Moderate) Monitor renal function during concomitant angiotensin-converting enzyme inhibitor and magnesium sulfate; potassium sulfate; sodium sulfate bowel preparation due to risk for renal injury; ensure adequate hydration. (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
Mannitol: (Major) Avoid use of other diuretics with mannitol, if possible. Concomitant administration may potentiate the renal toxicity of mannitol.
Meclofenamate Sodium: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Mefenamic Acid: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Meglitinides: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Meloxicam: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Memantine: (Minor) Memantine reduced the bioavailability of hydrochlorothiazide by roughly 20% in a drug interaction study. The clinical significance of this pharmacokinetic interaction, if any, is unknown.
Meperidine: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with meperidine. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Metaproterenol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Metformin; Repaglinide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Metformin; Rosiglitazone: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Metformin; Saxagliptin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Metformin; Sitagliptin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Methadone: (Moderate) Diuretics can cause electrolyte disturbances such as hypomagnesemia and hypokalemia, which may prolong the QT interval. As methadone may also prolong the QT interval, cautious coadministration with diuretics is needed. In addition, opiate agonists may potentiate orthostatic hypotension when used concurrently with diuretics.
Methamphetamine: (Minor) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, like angiotensin-converting enzyme inhibitors (ACE inhibitors). Close monitoring of blood pressure is advised. (Minor) Amphetamines may counteract the activity of some antihypertensive agents, such as thiazide diuretics. Close monitoring of blood pressure is advised. Thiazide diuretics may also increase and prolong the actions of amphetamines by increasing the urinary pH.
Methazolamide: (Moderate) Thiazide diuretics may increase the risk of hypokalemia if used concurrently with methazolamide. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. There may also be an additive diuretic or hyperuricemic effect.
Methenamine: (Moderate) Thiazide diuretics may cause the urine to become alkaline. This may reduce the effectiveness of methenamine by inhibiting its conversion to formaldehyde.
Methenamine; Sodium Acid Phosphate: (Moderate) Thiazide diuretics may cause the urine to become alkaline. This may reduce the effectiveness of methenamine by inhibiting its conversion to formaldehyde.
Methenamine; Sodium Acid Phosphate; Methylene Blue; Hyoscyamine: (Moderate) Thiazide diuretics may cause the urine to become alkaline. This may reduce the effectiveness of methenamine by inhibiting its conversion to formaldehyde. (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Methenamine; Sodium Salicylate: (Moderate) Thiazide diuretics may cause the urine to become alkaline. This may reduce the effectiveness of methenamine by inhibiting its conversion to formaldehyde.
Methohexital: (Moderate) Concurrent use of methohexital and antihypertensive agents increases the risk of developing hypotension.
Methotrexate: (Moderate) Monitor for increased methotrexate-related adverse reactions during concomitant thiazide diuretic use. Thiazide diuretics may decrease renal excretion of cytotoxic agents and enhance their myelosuppressive effects.
Methoxsalen: (Moderate) Concomitant administration of methoxsalen and other photosensitizing agents, such as thiazide diuretics, can increase the incidence or severity of photsensitization from either compound.
Methscopolamine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Methylphenidate Derivatives: (Moderate) Monitor blood pressure during concomitant thiazide diuretic and methylphenidate use; a thiazide diuretic dose adjustment may be necessary. Methylphenidate may decrease the effectiveness of medications used to treat hypertension. (Moderate) Periodic evaluation of blood pressure is advisable during concurrent use of methylphenidate derivatives and antihypertensive agents, particularly during initial coadministration and after dosage increases of methylphenidate derivatives. Methylphenidate derivatives can reduce the hypotensive effect of antihypertensive agents such as angiotensin-converting enzyme inhibitors.
Metoclopramide: (Minor) Coadministration of thiazides and prokinetic agents may result in decreased bioavailability of the thiazide diuretic.
Midodrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly.
Miglitol: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Milnacipran: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discon tinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Milrinone: (Moderate) Concurrent administration of antihypertensive agents could lead to additive hypotension when administered with milrinone. Titrate milrinone dosage according to hemodynamic response.
Mirtazapine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and mirtazapine use; consider discontinuing mirtazapine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Mivacurium: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Moexipril: (Major) Discontinue the thiazide diuretic prior to starting moexipril, if possible, or start moexipril at the lower dose of 3.75 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Morphine: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and morphine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Morphine; Naltrexone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and morphine; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Nabumetone: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Nanoparticle Albumin-Bound Sirolimus: (Moderate) Sirolimus has been associated with the development of angioedema. The use of sirolimus with other drugs known to cause angioedema, such as angiotensin-converting enzyme inhibitors may increase the risk of developing angioedema. Patients should be monitored for angioedema if any of these drugs are coadministered with sirolimus.
Naproxen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Naproxen; Esomeprazole: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Monitor magnesium concentration before and periodically during concomitant esomeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Naproxen; Pseudoephedrine: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics. (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Nateglinide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Nebivolol; Valsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Nefazodone: (Minor) Although relatively infrequent, nefazodone may cause orthostatic hypotension in some patients; this effect may be additive with antihypertensive agents. Blood pressure monitoring and dosage adjustments of either drug may be necessary.
Neostigmine; Glycopyrrolate: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Nesiritide, BNP: (Major) The potential for hypotension may be increased when coadministering nesiritide with antihypertensive agents. (Moderate) The potential for hypotension may be increased when coadministering nesiritide with antihypertensive agents.
Neuromuscular blockers: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Niacin, Niacinamide: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
Niacin; Simvastatin: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
Nitrates: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and nitrate use due to risk for additive hypotension.
Nitroglycerin: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and nitrate use due to risk for additive hypotension.
Nitroprusside: (Moderate) Additive hypotensive effects may occur when nitroprusside is used concomitantly with other antihypertensive agents. Dosages should be adjusted carefully, according to blood pressure.
Non-Ionic Contrast Media: (Major) Do not use diuretics before non-ionic contrast media administration. Concomitant use of diuretics and non-ionic contrast media may increase the risk for acute kidney injury, including renal failure. (Moderate) Because the use of other nephrotoxic drugs, including ACE inhibitors, is an additive risk factor for nephrotoxicity in patients receiving radiopaque contrast agents, ACE inhibitor therapy should be withheld, when possible, during radiopaque contrast agent administration.
Nonsteroidal antiinflammatory drugs: (Moderate) Monitor blood pressure and renal function periodically during concomitant angiotensin-converting enzyme (ACE) inhibitor and nonsteroidal anti-inflammatory drug (NSAID) use. The antihypertensive effect of ACE inhibitors may be diminished by NSAIDs. In persons who are elderly, volume-depleted, or with compromised renal function, coadministration of ACE inhibitors and NSAIDs may result in deterioration of renal function, including possible acute renal failure; these effects are usually reversible. (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Norepinephrine: (Moderate) Thiazide diuretics can cause decreased arterial responsiveness to norepinephrine, but the effect is not sufficient to preclude their coadministration.
Octreotide: (Moderate) Patients receiving diuretics or other agents to control fluid and electrolyte balance may require dosage adjustments while receiving octreotide due to additive effects.
Olanzapine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olanzapine; Fluoxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and fluoxetine use; consider discontinuing fluoxetine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia. (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olanzapine; Samidorphan: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Oliceridine: (Moderate) Monitor patients for signs of diminished diuresis and/or effects on blood pressure if diuretics are used concomitantly with oliceridine; increase the dosage of the diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Olmesartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Olmesartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Olodaterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Omeprazole: (Moderate) Monitor magnesium concentration before and periodically during concomitant omeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Omeprazole; Amoxicillin; Rifabutin: (Moderate) Monitor magnesium concentration before and periodically during concomitant omeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Omeprazole; Sodium Bicarbonate: (Moderate) Monitor magnesium concentration before and periodically during concomitant omeprazole and thiazide diuretic use due to risk for hypomagnesemia.
Oxaprozin: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Oxybutynin: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Oxycodone: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and oxycodone; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Oxymetazoline: (Major) The vasoconstricting actions of oxymetazoline, an alpha adrenergic agonist, may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. If these drugs are used together, closely monitor for changes in blood pressure. (Major) The vasoconstricting actions of oxymetazoline, an alpha adrenergic agonist, may reduce the antihypertensive effects produced by diuretics. If these drugs are used together, closely monitor for changes in blood pressure.
Oxymorphone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with oxymorphone. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Paliperidone: (Moderate) Paliperidone may cause orthostatic hypotension, thereby enhancing the hypotensive effects of antihypertensive agents. Orthostatic vital signs should be monitored in patients receiving paliperidone and angiotensin-converting enzyme inhibitors who are susceptible to hypotension. (Moderate) Paliperidone may cause orthostatic hypotension, thereby enhancing the hypotensive effects of antihypertensive agents. Orthostatic vital signs should be monitored in patients receiving paliperidone and thiazide diuretics who are susceptible to hypotension.
Pancuronium: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Pantoprazole: (Moderate) Monitor magnesium concentration before and periodically during concomitant pantoprazole and thiazide diuretic use due to risk for hypomagnesemia.
Paroxetine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and paroxetine use; consider discontinuing paroxetine if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Pasireotide: (Moderate) Cautious use of pasireotide and thiazide diuretics is advised as electrolyte imbalance caused by diuretics may increase the risk of QT prolongation with pasireotide. Assess the patient's potassium and magnesium concentration before and periodically during pasireotide receipt. Correct hypokalemia and hypomagnesemia before pasireotide receipt.
Pentamidine: (Moderate) Drugs that are associated with hypokalemia and/or hypomagnesemia such as thiazide diuretics should be used with caution in patients also receiving pentamidine. Since pentamidine may cause QT prolongation independently of electrolyte imbalances, the risk for cardiac arrhythmias is potentiated by the concomitant use of agents associated with electrolyte loss. Closely monitor serum electrolytes during pentamidine therapy.
Pentazocine: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with pentazocine. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Pentazocine; Naloxone: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with pentazocine. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Pentoxifylline: (Moderate) Pentoxifylline has been used concurrently with antihypertensive drugs (beta blockers, diuretics) without observed problems. Small decreases in blood pressure have been observed in some patients treated with pentoxifylline; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensives. If indicated, dosage of the antihypertensive agents should be reduced.
Perindopril: (Major) Discontinue the thiazide diuretic prior to starting perindopril, if possible, or start perindopril at a lower dose to minimize hypotension. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Perindopril; Amlodipine: (Major) Discontinue the thiazide diuretic prior to starting perindopril, if possible, or start perindopril at a lower dose to minimize hypotension. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Phendimetrazine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly.
Phenelzine: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with angiotensin-converting enzyme inhibitors (ACE inhibitors). Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and phenelzine use due to risk for additive hypotension.
Phenobarbital; Hyoscyamine; Atropine; Scopolamine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Phenothiazines: (Moderate) Monitor blood pressure during concomitant thiazide diuretic and phenothiazine use. Thiazide diuretics may potentiate the orthostatic hypotension that may occur with phenothiazines.
Phentermine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly.
Phentermine; Topiramate: (Moderate) Monitor serum potassium concentrations and for increased topiramate-related adverse effects during concomitant hydrochlorothiazide use. Concomitant use has been shown to increase topiramate exposure by 29% and may potentiate the potassium-wasting action of hydrochlorothiazide. (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly.
Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Photosensitizing agents (topical): (Moderate) Thiazide diuretics may cause photosensitivity and may increase the photosensitization effects of photosensitizing agents used in photodynamic therapy. Prevention of photosensitivity includes adequate protection from sources of UV radiation (e.g., avoiding sun exposure and tanning booths) and the use of protective clothing and sunscreens on exposed skin.
Pimozide: (Moderate) Caution is advisable during concurrent use of pimozide and thiazide diuretics as electrolyte imbalance caused by diuretics may increase the risk of QT prolongation with pimozide. Potassium deficiencies should be corrected prior to treatment with pimozide and normalized potassium levels should be maintained during treatment.
Pioglitazone: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Pioglitazone; Glimepiride: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Pioglitazone; Metformin: (Moderate) Certain drugs, such as thiazide diuretics, tend to produce hyperglycemia and may lead to loss of glycemic control. The effects of thiazide diuretics on glycemic control appear to be dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, thiazide diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. Patients receiving metformin should be monitored for changes in blood glucose control if any of these diuretics are added or deleted. Dosage adjustments may be necessary in some patients. (Moderate) Monitor blood glucose during concomitant metformin and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Piroxicam: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Polycarbophil: (Moderate) Coadministration may lead to hypercalcemia because thiazides cause a decrease in renal tubular excretion of calcium as well as increase in distal tubular reabsorption. Each 625 mg of calcium polycarbophil contains a substantial amount of calcium (approximately 125 mg). Moderate increases in serum calcium have been seen during the treatment with thiazides; if calcium polycarbophil is used concomitantly, monitoring of serum calcium may be prudent.
Polyethylene Glycol; Electrolytes: (Moderate) Monitor renal function during concomitant angiotensin-converting enzyme inhibitor and magnesium sulfate; potassium sulfate; sodium sulfate bowel preparation due to risk for renal injury; ensure adequate hydration. (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
Polyethylene Glycol; Electrolytes; Ascorbic Acid: (Moderate) Monitor renal function during concomitant angiotensin-converting enzyme inhibitor and magnesium sulfate; potassium sulfate; sodium sulfate bowel preparation due to risk for renal injury; ensure adequate hydration. (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
Porfimer: (Major) Avoid coadministration of porfimer with thiazide diuretics due to the risk of increased photosensitivity. Porfimer is a light-activated drug used in photodynamic therapy; all patients treated with porfimer will be photosensitive. Concomitant use of other photosensitizing agents like thiazide diuretics may increase the risk of a photosensitivity reaction.
Potassium Phosphate: (Major) Avoid coadministration of potassium phosphate and angiotensin-converting enzyme inhibitors as concurrent use may increase the risk of severe and potentially fatal hyperkalemia, particularly in high-risk patients (renal impairment, cardiac disease, adrenal insufficiency). If concomitant use is necessary, closely monitor serum potassium concentrations.
Potassium Phosphate; Sodium Phosphate: (Major) Avoid coadministration of potassium phosphate and angiotensin-converting enzyme inhibitors as concurrent use may increase the risk of severe and potentially fatal hyperkalemia, particularly in high-risk patients (renal impairment, cardiac disease, adrenal insufficiency). If concomitant use is necessary, closely monitor serum potassium concentrations.
Potassium: (Moderate) Monitor serum potassium concentrations closely if potassium supplements and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. Concomitant use may increase the risk of hyperkalemia.
Pramlintide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Prazosin: (Moderate) Prazosin is well-known to produce a 'first-dose' phenomenon. Some patients develop significant hypotension shortly after administration of the first dose. The first dose response (acute postural hypotension) of prazosin may be exaggerated in patients who are receiving beta-adrenergic blockers, diuretics, or other antihypertensive agents. Concomitant administration of prazosin with other antihypertensive agents is not prohibited, however. This can be therapeutically advantageous, but lower dosages of each agent should be used. (Moderate) Prazosin is well-known to produce a 'first-dose' phenomenon. Some patients develop significant hypotension shortly after administration of the first dose. The first dose response (acute postural hypotension) of prazosin may be exaggerated in patients who are receiving beta-adrenergic blockers, diuretics, or other antihypertensive agents. Concomitant administration of prazosin with other antihypertensive agents is not prohibited, however. This can be therapeutically advantageous, but lower dosages of each agent should be used.
Pregabalin: (Moderate) Monitor for signs and symptoms of angioedema during concomitant angiotensin-converting enzyme inhibitor and pregabalin use. Concomitant use may increase the risk of developing angioedema.
Prilocaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine. (Moderate) Monitor blood pressure and heart rate during concomitant epinephrine and thiazide diuretic use. Thiazide diuretics may antagonize the pressor effects and potentiate the arrhythmogenic effects of epinephrine.
Probenecid: (Moderate) Probenecid decreases the renal tubular secretion of captopril, resulting in higher captopril serum concentrations. If probenecid is given to a patient stabilized on captopril, hypotension may occur. This interaction would appear to be of lesser significance if captopril is added after probenecid therapy is in place. (Moderate) Thiazide diuretics can cause hyperuricemia. Although this effect represents a pharmacodynamic interaction and not a pharmacokinetic one, dosage adjustments of probenecid may be necessary if these agents are administered concurrently to patients being treated with probenecid.
Probenecid; Colchicine: (Moderate) Probenecid decreases the renal tubular secretion of captopril, resulting in higher captopril serum concentrations. If probenecid is given to a patient stabilized on captopril, hypotension may occur. This interaction would appear to be of lesser significance if captopril is added after probenecid therapy is in place. (Moderate) Thiazide diuretics can cause hyperuricemia. Although this effect represents a pharmacodynamic interaction and not a pharmacokinetic one, dosage adjustments of probenecid may be necessary if these agents are administered concurrently to patients being treated with probenecid.
Procainamide: (Moderate) Procainamide can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents. Intravenous administration of procainamide is more likely to cause hypotensive effects.
Promethazine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Well-controlled hypertensive patients receiving phenylephrine at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure (especially systolic hypertension) has been reported in some patients. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
Propantheline: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Propofol: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents. (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Pseudoephedrine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Pseudoephedrine; Triprolidine: (Moderate) Sympathomimetics can antagonize the effects of antihypertensives when administered concomitantly. (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Quinapril: (Major) Discontinue the thiazide diuretic prior to starting quinapril, if possible, or start quinapril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Quinapril; Hydrochlorothiazide, HCTZ: (Major) Discontinue the thiazide diuretic prior to starting quinapril, if possible, or start quinapril at the lower dose of 5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
Rabeprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with thiazide diuretics (chlorothiazide, hydrochlorothiazide, indapamide, and metolazone). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
Ramipril: (Major) Discontinue the thiazide diuretic prior to starting ramipril, if possible, or start ramipril at a lower dose to minimize hypotension. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Rasagiline: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with angiotensin-converting enzyme inhibitors (ACE inhibitors). Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider. (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with diuretics. Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
Remifentanil: (Moderate) Opiate agonists may potentiate orthostatic hypotension when used concurrently with thiazide diuretics.
Repaglinide: (Moderate) ACE inhibitors may enhance the hypoglycemic effects of insulin or other antidiabetic agents by improving insulin sensitivity. Patients receiving antidiabetic agents can become hypoglycemic if ACE inhibitors are administered concomitantly. Patients receiving these drugs concomitantly with antidiabetic agents should be monitored for changes in glycemic control. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Risperidone: (Moderate) Risperidone may induce orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses or slower dose titration of risperidone may be necessary in patients receiving antihypertensive agents concomitantly.
Rocuronium: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Rosiglitazone: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Sacubitril; Valsartan: (Contraindicated) Sacubitril; valsartan is contraindicated with the concomitant use of angiotensin-converting enzyme inhibitors (ACE inhibitors) due to the increased risk of angioedema. Do not administer sacubitril; valsartan within 36 hours of switching to or from an ACE inhibitor. (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Salicylates: (Moderate) Aspirin, ASA may reduce the vasodilatory efficacy of ACE inhibitors by inhibiting the synthesis of vasodilatory prostaglandins. This interaction has been documented primarily in heart failure patients. However, the established benefits of using aspirin in combination with an ACE inhibitor in patients with ischemic heart disease and left ventricular dysfunction generally outweigh this concern. Patients receiving concurrent salicylates and ACE inhibitor therapy should be monitored for antihypertensive or vasodilatory efficacy; the dose of the ACE inhibitor can be adjusted if indicated based on clinical evaluation. (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant thiazide diuretic and salicylate use. Salicylate use decreases glomerular filtration rate and renal blood flow, and concomitant diuretic use may increase the risk of this reaction. Salicylates may diminish the effectiveness of diuretics due to inhibition of renal prostaglandins, leading to decreased renal blood flow and salt and fluid retention.
Salmeterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Saxagliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Scopolamine: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Semaglutide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Serotonin norepinephrine reuptake inhibitors: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Sertraline: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and sertraline use; consider discontinuing sertraline if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Sevoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents. (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
SGLT2 Inhibitors: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
Silodosin: (Moderate) During clinical trials with silodosin, the incidence of dizziness and orthostatic hypotension was higher in patients receiving concomitant antihypertensive treatment. Thus, caution is advisable when silodosin is administered with antihypertensive agents. (Moderate) During clinical trials with silodosin, the incidence of dizziness and orthostatic hypotension was higher in patients receiving concomitant antihypertensive treatment. Thus, caution is advisable when silodosin is administered with antihypertensive agents.
Sirolimus: (Moderate) Sirolimus has been associated with the development of angioedema. The use of sirolimus with other drugs known to cause angioedema, such as angiotensin-converting enzyme inhibitors may increase the risk of developing angioedema. Patients should be monitored for angioedema if any of these drugs are coadministered with sirolimus.
Sitagliptin: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as angiotensin-converting enzyme inhibitors, may increase the risk of acute phosphate nephropathy in patients taking sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous. (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as diuretics, may increase the risk of acute phosphate nephropathy in patients taking sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous.
Sodium picosulfate; Magnesium oxide; Anhydrous citric acid: (Moderate) Use caution when prescribing sodium picosulfate; magnesium oxide; anhydrous citric acid in patients taking concomitant medications that may affect renal function such as angiotensin-converting enzyme inhibitors (ACE inhibitors). In addition, use caution in patients receiving drugs where hypokalemia is a particular risk. (Moderate) Use caution when prescribing sodium picosulfate; magnesium oxide; anhydrous citric acid in patients taking concomitant medications that may affect renal function such as diuretics. In addition, use caution in patients receiving drugs where hypokalemia is a particular risk.
Sodium Sulfate; Magnesium Sulfate; Potassium Chloride: (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as angiotensin-converting enzyme inhibitors (ACE inhibitors).
Solifenacin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms. Risk versus benefit should be addressed in patients receiving diuretics and solifenacin.
Sparsentan: (Major) Hold angiotensin-converting enzyme inhibitor therapy when initiating sparsentan and until a stable dose of sparsentan is achieved. Frequently monitor potassium during concomitant use due to the increased risk for hyperkalemia.
Spironolactone: (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and spironolactone are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Spironolactone; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and spironolactone are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Streptozocin: (Minor) Because streptozocin is nephrotoxic, concurrent or subsequent administration of other nephrotoxic agents (e.g., aminoglycosides, amphotericin B, cisplatin, foscarnet, or diuretics) could exacerbate the renal insult.
Succinylcholine: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Sufentanil: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with sufentanil. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Sulfacetamide: (Moderate) Sulfonamides may cause photosensitization and may increase the photosensitizing effects of thiazide diuretics.
Sulfacetamide; Sulfur: (Moderate) Sulfonamides may cause photosensitization and may increase the photosensitizing effects of thiazide diuretics.
Sulfamethoxazole; Trimethoprim, SMX-TMP, Cotrimoxazole: (Major) Avoid the concomitant use of sulfamethoxazole; trimethoprim and thiazide diuretics. An increased incidence of thrombocytopenia with purpura has been reported in elderly patients during coadministration. (Moderate) Monitor for hyperkalemia if concomitant use of an angiotensin-converting enzyme (ACE) inhibitor and trimethoprim is necessary. Avoid concomitant use and consider alternative antibiotic therapy in patients with additional risk factors for hyperkalemia, including patients older than 65 years, those with underlying disorders of potassium metabolism, renal insufficiency, or those requiring high doses of trimethoprim. Amongst patients older than 65 years, concomitant use has been associated with a 2- to 7-fold increased risk of significant hyperkalemia compared to other antibiotics. Trimethoprim has a potassium-sparing effect on the distal nephron and may induce hyperkalemia, especially in those with pre-existing risk factors.
Sulfonylureas: (Moderate) Monitor blood glucose during concomitant sulfonylurea and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Sulindac: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Sumatriptan; Naproxen: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Tacrolimus: (Moderate) Tacrolimus, in the absence of overt renal impairment, may adversely affect renal function. Care should be taken in using tacrolimus with other nephrotoxic drugs, including ACE inhibitors.
Tapentadol: (Moderate) Monitor for decreased diuretic efficacy and additive orthostatic hypotension when thiazide diuretics are administered with tapentadol. Adjustments to diuretic therapy may be needed in some patients. The efficacy of diuretics may be reduced due to opioid-induced release of antidiuretic hormone.
Tazarotene: (Moderate) The manufacturer states that tazarotene should be administered with caution in patients who are also taking drugs known to be photosensitizers, such as thiazide diuretics, as concomitant use may augment phototoxicity. Patients should take care and use proper techniques to limit sunlight and UV exposure of treated areas.
Tegaserod: (Minor) Coadminisitration of thiazides and prokinetic agents may result in decreased bioavailability of the thiazide diuretic.
Telavancin: (Moderate) Concurrent or sequential use of telavancin with other potentially nephrotoxic drugs such as Angiotensin-converting enzyme inhibitors (ACE inhibitors) may lead to additive nephrotoxicity. Closely monitor renal function and adjust telavancin doses based on calculated creatinine clearance.
Telmisartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Telmisartan; Amlodipine: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Telmisartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Temsirolimus: (Moderate) Monitor for signs and symptoms of angioedema if temsirolimus is administered concomitantly with captopril. Angioedema has been reported in patients taking mammalian target of rapamycin (mTOR) inhibitors in combination with another ACE inhibitor.
Terbutaline: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Tetrabenazine: (Moderate) Tetrabenazine may induce orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses or slower dose titration of tetrabenazine may be necessary in patients receiving antihypertensive agents concomitantly. (Moderate) Tetrabenazine may induce orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses or slower dose titration of tetrabenazine may be necessary in patients receiving antihypertensive agents concomitantly.
Tetracaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of tetracaine and antihypertensive agents.
Th iazide diuretics: (Major) Discontinue the thiazide diuretic prior to starting captopril, if possible, or start captopril at the lower dose of 6.25 or 12.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Thiazolidinediones: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and angiotensin-converting enzyme (ACE) inhibitor use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Thiothixene: (Moderate) Thiothixene should be used cautiously in patients receiving antihypertensive agents. Additive hypotensive effects are possible.
Tiotropium; Olodaterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Tirzepatide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. Finally, both thiazides and sulfonylureas have been reported to cause photosensitivity reactions; concomitant use may increase the risk of photosensitivity.
Tizanidine: (Moderate) Concurrent use of tizanidine with antihypertensive agents can result in significant hypotension. Caution is advised when tizanidine is to be used in patients receiving concurrent antihypertensive therapy. (Moderate) Monitor blood pressure during concomitant thiazide diuretic and tizanidine use due to risk for additive hypotension.
Tolazamide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Tolbutamide: (Moderate) Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Diuretic-induced hypokalemia may also lead to hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between thiazide diuretics and antidiabetic agents. It appears that the effects of thiazide diuretics on glycemic control are dose-related and low doses can be instituted without deleterious effects on glycemic control. In addition, diuretics reduce the risk of stroke and cardiovascular disease in patients with diabetes. However, patients taking antidiabetic agents should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
Tolmetin: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Tolterodine: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Tolvaptan: (Moderate) Monitor serum potassium concentrations closely if tolvaptan and angiotensin-converting enzyme inhibitors (ACE inhibitors) are used together. In clinical studies, hyperkalemia was reported at a rate 1% to 2% higher when tolvaptan was administered with ACE inhibitors compared to administration of these medications with placebo. (Moderate) Monitor serum sodium closely if tolvaptan and thiazide diuretics are used together. Coadministration increases the risk of too rapid correction of serum sodium.
Topiramate: (Moderate) Monitor serum potassium concentrations and for increased topiramate-related adverse effects during concomitant hydrochlorothiazide use. Concomitant use has been shown to increase topiramate exposure by 29% and may potentiate the potassium-wasting action of hydrochlorothiazide.
Toremifene: (Moderate) Monitor serum calcium levels in patients receiving concomitant treatment with toremifene and thiazide diuretics. Thiazide diuretics decrease renal calcium excretion and may increase the risk of hypercalcemia in patients receiving toremifene.
Tramadol: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and tramadol; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Tramadol; Acetaminophen: (Moderate) Monitor for signs of diminished diuresis and/or effects on blood pressure during coadministration of a thiazide diuretic and tramadol; increase the dosage of the thiazide diuretic as needed. Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Opioids may also potentiate orthostatic hypotension when given concomitantly with a thiazide diuretic.
Trandolapril: (Major) Discontinue the thiazide diuretic prior to starting trandolapril, if possible, or start trandolapril at the lower dose of 0.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Trandolapril; Verapamil: (Major) Discontinue the thiazide diuretic prior to starting trandolapril, if possible, or start trandolapril at the lower dose of 0.5 mg/day. Monitor blood pressure, particularly when doses are increased, and renal function during concomitant use. Concomitant use may increase the risk for hypotension or renal failure.
Tranylcypromine: (Contraindicated) The use of hypotensive agents and tranylcypromine is contraindicated by the manufacturer of tranylcypromine because the effects of hypotensive agents may be markedly potentiated.
Trazodone: (Minor) Due to additive hypotensive effects, patients receiving antihypertensive agents concurrently with trazodone may have excessive hypotension. Decreased dosage of the antihypertensive agent may be required when given with trazodone.
Treprostinil: (Moderate) Thiazide diuretics can enhance the hypotensive effects of antihypertensive agents or diuretics if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly.
Tretinoin, ATRA: (Moderate) A manufacturer of topical tretinoin states that tretinoin, ATRA should be administered with caution in patients who are also taking drugs known to be photosensitizers, such as thiazide diuretics, as concomitant use may augment phototoxicity. Patients should take care and use proper techniques to limit sunlight and UV exposure of treated areas.
Tretinoin; Benzoyl Peroxide: (Moderate) A manufacturer of topical tretinoin states that tretinoin, ATRA should be administered with caution in patients who are also taking drugs known to be photosensitizers, such as thiazide diuretics, as concomitant use may augment phototoxicity. Patients should take care and use proper techniques to limit sunlight and UV exposure of treated areas.
Triamterene: (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and triamterene are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Triamterene; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum potassium concentrations closely if ACE inhibitors and triamterene are used together. Concomitant use may increase the risk of hyperkalemia, especially in elderly patients or patients with impaired renal function.
Trihexyphenidyl: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Trimethoprim: (Moderate) Monitor for hyperkalemia if concomitant use of an angiotensin-converting enzyme (ACE) inhibitor and trimethoprim is necessary. Avoid concomitant use and consider alternative antibiotic therapy in patients with additional risk factors for hyperkalemia, including patients older than 65 years, those with underlying disorders of potassium metabolism, renal insufficiency, or those requiring high doses of trimethoprim. Amongst patients older than 65 years, concomitant use has been associated with a 2- to 7-fold increased risk of significant hyperkalemia compared to other antibiotics. Trimethoprim has a potassium-sparing effect on the distal nephron and may induce hyperkalemia, especially in those with pre-existing risk factors.
Trospium: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Umeclidinium; Vilanterol: (Minor) Hypokalemia associated with thiazide diuretics can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is unknown, use caution when coadministering beta-agonists with thiazide diuretics and monitor serum potassium as clinically indicated.
Valdecoxib: (Moderate) Monitor blood pressure as well as for signs of worsening renal function and loss of diuretic efficacy, including antihypertensive effects, during concomitant nonsteroidal antiinflammatory drug (NSAID) and thiazide diuretic use. NSAIDs may cause a dose-dependent reduction in renal blood flow, which may precipitate overt renal decompensation, and concomitant diuretic use increases the risk of this reaction. NSAIDs have been shown to reduce the natriuretic effect of thiazide diuretics and are associated with fluid retention which may blunt the cardiovascular effects of diuretics.
Valsartan: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Valsartan; Hydrochlorothiazide, HCTZ: (Major) In general, avoid combined use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) due to lack of benefit with concomitant use in most patients. Closely monitor blood pressure, renal function, and electrolytes in patients on ACE inhibitors and ARBs. Dual blockade of the renin-angiotensin system with ACE inhibitors and ARBs is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function, including acute renal failure, compared to monotherapy.
Vecuronium: (Moderate) Concomitant use of neuromuscular blockers and thiazide diuretics may prolong neuromuscular blockade, possibly due to hypokalemia or alterations in potassium concentrations across the end-plate membrane.
Venlafaxine: (Moderate) Monitor for signs and symptoms of hyponatremia during concomitant diuretic and serotonin norepinephrine reuptake inhibitor (SNRI) use; consider discontinuing the SNRI if symptomatic hyponatremia occurs and institute appropriate medical intervention. Concomitant use increases the risk for developing hyponatremia.
Verteporfin: (Moderate) Use caution if coadministration of verteporfin with thiazide diuretics is necessary due to the risk of increased photosensitivity. Verteporfin is a light-activated drug used in photodynamic therapy; all patients treated with verteporfin will be photosensitive. Concomitant use of other photosensitizing agents like thiazide diuretics may increase the risk of a photosensitivity reaction.
Vilazodone: (Moderate) Patients receiving vilazodone with medications known to cause hyponatremia, such as diuretics, may be at increased risk of developing hyponatremia. Hyponatremia has occurred in association with the use of antidepressants such as selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), and mirtazapine. Hyponatremia may manifest as headache, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness which may result in falls. Severe manifestations include hallucinations, syncope, seizure, coma, respiratory arrest, and death. Symptomatic hyponatremia may require discontinuation of vilazodone, as well as implementation of the appropriate medical interventions.
Vitamin D analogs: (Moderate) Monitor serum calcium concentrations during concomitant use of thiazide diuretics and vitamin D analogs; a dosage adjustment of the vitamin D analog may be needed. Hypercalcemia may be exacerbated by concomitant administration.
Vitamin D: (Moderate) Dose adjustment of vitamin D or vitamin D analogs may be necessary during coadministration with thiazide diuretics. Additionally, serum calcium concentrations should be monitored frequently. Monitor more frequently in patients with a history of hypercalcemia. Hypercalcemia may be exacerbated by coadministration of vitamin D or vitamin D analogs and thiazide diuretics. Thiazide diuretics are known to induce hypercalcemia by reducing the excretion of calcium in the urine.
Vitamin D: (Moderate) Dose adjustment of vitamin D or vitamin D analogs may be necessary during coadministration with thiazide diuretics. Additionally, serum calcium concentrations should be monitored frequently. Monitor more frequently in patients with a history of hypercalcemia. Hypercalcemia may be exacerbated by coadministration of vitamin D or vitamin D analogs and thiazide diuretics. Thiazide diuretics are known to induce hypercalcemia by reducing the excretion of calcium in the urine.
Vorinostat: (Moderate) Use vorinostat and thiazide diuretics together with caution; the risk of QT prolongation and arrhythmias may be increased if electrolyte abnormalities occur. Thiazide diuretics may cause electrolyte imbalances including low potassium; hypomagnesemia, hypokalemia, or hypocalcemia may increase the risk of QT prolongation with vorinostat. Frequently monitor serum electrolytes if concomitant use of these drugs is necessary.
Vortioxetine: (Moderate) Patients receiving a diuretic during treatment with vortioxetine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Clinically significant hyponatremia has been reported during therapy with vortioxetine. One case involving serum sodium levels lower than 110 mmol/l has occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of vortioxetine should be considered in patients who develop symptomatic hyponatremia.
Ziconotide: (Moderate) Patients taking diuretics with ziconotide may be at higher risk of depressed levels of consciousness. If altered consciousness occurs, consideration of diuretic cessation is warranted in addition to ziconotide discontinuation.
Ziprasidone: (Moderate) Monitor potassium and magnesium levels when thiazide diuretics are used during ziprasidone therapy. The risk of QT prolongation from ziprasidone is increased in the presence of hypokalemia or hypomagnesemia. (Minor) Ziprasidone is a moderate antagonist of alpha-1 receptors and may cause orthostatic hypotension with or without tachycardia, dizziness, or syncope. Additive hypotensive effects are possible if ziprasidone is used concurrently with antihypertensive agents.

How Supplied

Capozide/Captopril, Hydrochlorothiazide Oral Tab: 25-15mg, 25-25mg, 50-15mg, 50-25mg

Maximum Dosage
Adults

150 mg/day PO captopril and 50 mg/day PO hydrochlorothiazide.

Geriatric

150 mg/day PO captopril and 50 mg/day PO hydrochlorothiazide.

Adolescents

150 mg/day PO captopril and 50 mg/day PO hydrochlorothiazide.

Children

Maximum dosage information is not available for the combination product.

Mechanism Of Action

The effects of captopril and hydrochlorothiazide on blood pressure are additive. Thiazide diuretics lower the blood pressure by increasing the excretion of sodium; whereas ACE inhibitors lower blood pressure by blocking the renin-angiotensin system. Captopril can counteract the hypokalemia caused by the hydrochlorothiazide.
 
•Hydrochlorothiazide: Thiazide diuretics increase the excretion of water by inhibiting the reabsorption of sodium and chloride ions at the distal renal tubule. The natriuretic effects are accompanied by a secondary loss of potassium and bicarbonate which can cause a mild hypokalemic, hypochloremic, metabolic alkalosis. Thiazides also decrease the elimination of calcium and uric acid. Thiazides diuretics usually do not affect normal blood pressure. When chronically administered, diuretics decrease peripheral vascular resistance. The exact mechanism responsible for the lowered peripheral resistance is not known; however, excretion of urinary sodium by the kidneys is required to achieve blood pressure reduction. Initially, diuretics lower blood pressure by decreasing cardiac output, plasma volume and extracellular fluid volume. Cardiac output eventually returns to normal, plasma and extracellular fluid values return to slightly less than normal, but peripheral vascular resistance is reduced, resulting in lower blood pressure. Thiazide diuretics also decrease the glomerular filtration rate, which contributes to the drug's lower efficacy in patients with renal impairment. The changes in plasma volume induce an elevation in plasma renin activity and aldosterone secretion which contributes to the potassium losses associated with thiazide diuretics. In general, diuretics can worsen glucose tolerance and lipid abnormalities.
 
•Captopril: Captopril competes with angiotensin-converting enzyme (ACE) for the substrate angiotensin I, thereby blocking its conversion to angiotensin II. Angiotensin II is a potent vasoconstrictor and a negative-feedback mediator for renin activity. Thus, when captopril lowers angiotensin II plasma levels, blood pressure decreases and plasma renin activity increases. In addition, baroreceptor reflex mechanisms are stimulated in response to the fall in blood pressure. ACE inhibition also blocks the conversion of bradykinin, a potent vasodilator, to inactive peptides. Whether increased bradykinin levels play a part in the therapeutic effects of ACE inhibitors is presently unclear. Bradykinin-induced vasodilation is thought to be of secondary importance in the blood-pressure lowering effect of ACE inhibitors. A bradykinin mechanism may, however, contribute to ACE-inhibitor-induced angioneurotic edema and cough.
 
ACE-inhibiting drugs may act locally to reduce vascular tone by decreasing local angiotensin II-induced sympathetic and/or vasoconstrictive activity. Decreases in plasma angiotensin II levels also reduce aldosterone secretion, subsequently decreasing sodium and water retention.
 
Captopril dilates arterioles, thereby lowering total peripheral vascular resistance. In hypertensive patients, blood pressure is decreased with little or no change in heart rate, stroke volume, or cardiac output. Both standing and supine blood pressure are reduced following administration of captopril, and although symptomatic hypotension is rare, it occurs more often in patients who are hypovolemic or hyponatremic. As antihypertensives, ACE inhibitors reduce LVH, do not worsen insulin resistance or hyperlipidemia, and generally do not cause sexual dysfunction.

Pharmacokinetics

Captopril; hydrochlorothiazide is administered orally. Concomitant administration of captopril with hydrochlorothiazide has no effect on the bioavailability of either drug. 
Captopril: Captopril distributes into most body tissues, and approximately 25% is bound to plasma proteins. The drug is metabolized (50%) in the liver to inactive metabolites, followed by excretion of the unchanged drug and its metabolites in the urine. Captopril renal elimination occurs primarily by tubular excretion. In patients with normal renal function, the half-life of captopril is less than 2 hours. The pharmacokinetics and elimination of captopril are not affected by age or congestive heart failure.
Hydrochlorothiazide: Hydrochlorothiazide crosses the placenta, but not the blood-brain barrier, and is distributed into breast milk. Hydrochlorothiazide is not significantly metabolized and is excreted unchanged in the urine. The elimination half-life ranges from 5.6—14.8 hours.

Oral Route

Captopril: Captopril is rapidly absorbed from the GI tract. If given with food, absorption decreases by 30—40%. Food decreases the absorption of captopril following administration of the combination product by 20—40%. Noticeable antihypertensive effects of captopril begin within 15 minutes; maximum beneficial effects require several weeks of therapy. The effects of a dose of captopril generally last about 2—6 hours, but the duration of action can be prolonged in patients with renal dysfunction. 
Hydrochlorothiazide: Hydrochlorothiazide absorption from the GI tract varies depending on the formulation, dose, and presence of concomitant disease states. Absorption is reduced in patients with hepatic, cardiac, and/or renal disease. The bioavailability is approximately 60—70%. The onset of action is 2 hours following oral administration, with peak effects occurring at 4 hours. The duration of action ranges from 6—12 hours.

Pregnancy And Lactation
Pregnancy

Captopril; hydrochlorothiazide is classified as FDA pregnancy risk category C in the first trimester and D in the second and third trimester. Based on the results from one large study, first trimester use of thiazide and related diuretics may increase the risk for congenital defects (pregnancy category D). In addition to malformations, other fetal risks associated with thiazide use during pregnancy include hypoglycemia, thrombocytopenia, hyponatremia, hypokalemia, and death from maternal complications. ACE inhibitors have been associated with fetal and neonatal morbidity and mortality when administered to pregnant women. In women planning to become pregnant, ACE inhibitors should not be used. Women of child-bearing age should be made aware of the potential risk and ACE inhibitors should only be given after careful counseling and consideration of individual risks and benefits. When pregnancy is detected, ACE inhibitors should be discontinued as soon as possible and monitoring of the fetal development should be performed on a regular basis. Rarely (probably less often than once per every thousand pregnancies), no alternative to ACE inhibitors will be found. In these rare cases, the pregnant women should be apprised of the potential hazards to their fetuses, and serial ultrasound examinations should be performed to assess the intraamniotic environment. The reported adverse fetal and neonatal effects (e.g., hypotension, neonatal skull hypoplasia and craniofacial deformation, fetal limb contractures, hypoplastic lung development, anuria, oligohydramnios, reversible or irreversible renal failure, and death) have been reported during ACE inhibitor exposure during the second and third trimesters. In addition, an observational study based on Tennessee Medicaid data reported that the risk of congenital malformations is significantly increased during first-trimester exposure to ACE inhibitors. However, a much larger observational study (n = 465,754) found that the risk of birth defects was similar in infants exposed to ACE inhibitors during the first trimester, in infants exposed to other antihypertensives during the first trimester, and in those whose mothers were hypertensive but were not treated. Infants born to mothers with hypertension, either treated or untreated, had a higher risk of birth defects than those born to mothers without hypertension. The authors concluded that the presence of hypertension likely contributed to the development of birth defects rather than the use of medications. Further evaluation of teratogenicity data associated with ACE inhibitor exposure during pregnancy is ongoing.

According to the manufacturer, hydrochlorothiazide and captopril have been detected in human breast milk. Due to low levels in breast milk, guidelines generally consider captopril to be compatible with breast-feeding unless high doses are required. Hydrochlorothiazide distributes into breast milk at low quantities and is usually considered compatible with breast-feeding. High hydrochlorothiazide dosages (100 mg to 150 mg/day) have been used to suppress lactation. Suppression of lactation has not been reported with hydrochlorothiazide doses of 50 mg or less. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition.