Capoten

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Capoten

Classes

Angiotensin Converting Enzyme Inhibitors/ACEIs

Administration

For storage information, see the specific product  information within the How Supplied section.

Oral Administration

To ensure maximum absorption, administer on an empty stomach 1 hour before meals. Drug absorption is reduced 30—40% by food.

Adverse Reactions
Severe

peptic ulcer / Delayed / 0.5-2.0
hepatic failure / Delayed / 0-1.0
hepatic necrosis / Delayed / 0-1.0
heart failure / Delayed / 0.2-0.3
myocardial infarction / Delayed / 0.2-0.3
oliguria / Early / 0.1-0.2
nephrotic syndrome / Delayed / 0.1-0.2
renal failure (unspecified) / Delayed / 0.1-0.2
hemolytic anemia / Delayed / Incidence not known
aplastic anemia / Delayed / Incidence not known
pancytopenia / Delayed / Incidence not known
agranulocytosis / Delayed / Incidence not known
cardiac arrest / Early / Incidence not known
arrhythmia exacerbation / Early / Incidence not known
eosinophilic pneumonia / Delayed / Incidence not known
bronchospasm / Rapid / Incidence not known
vasculitis / Delayed / Incidence not known
Stevens-Johnson syndrome / Delayed / Incidence not known
erythema multiforme / Delayed / Incidence not known
exfoliative dermatitis / Delayed / Incidence not known
angioedema / Rapid / Incidence not known
anaphylactoid reactions / Rapid / Incidence not known
hyperkalemia / Delayed / Incidence not known
pancreatitis / Delayed / Incidence not known
teratogenesis / Delayed / Incidence not known

Moderate

constipation / Delayed / 0.5-2.0
dyspnea / Early / 0.5-2.0
proteinuria / Delayed / 1.0-1.0
palpitations / Early / 1.0-1.0
chest pain (unspecified) / Early / 1.0-1.0
sinus tachycardia / Rapid / 1.0-1.0
angina / Early / 0.2-0.3
thrombocytopenia / Delayed / Incidence not known
neutropenia / Delayed / Incidence not known
anemia / Delayed / Incidence not known
glossitis / Early / Incidence not known
orthostatic hypotension / Delayed / Incidence not known
hypotension / Rapid / Incidence not known
eosinophilia / Delayed / Incidence not known
hepatitis / Delayed / Incidence not known
elevated hepatic enzymes / Delayed / Incidence not known
cholestasis / Delayed / Incidence not known
jaundice / Delayed / Incidence not known
hyponatremia / Delayed / Incidence not known
ataxia / Delayed / Incidence not known
depression / Delayed / Incidence not known
confusion / Early / Incidence not known
blurred vision / Early / Incidence not known
myasthenia / Delayed / Incidence not known

Mild

pruritus / Rapid / 2.0-7.0
maculopapular rash / Early / 4.0-7.0
pallor / Early / 2.0-5.0
dysgeusia / Early / 2.0-4.0
vomiting / Early / 0.5-2.0
anorexia / Delayed / 0.5-2.0
diarrhea / Early / 0.5-2.0
abdominal pain / Early / 0.5-2.0
xerostomia / Early / 0.5-2.0
nausea / Early / 0.5-2.0
cough / Delayed / 0.5-2.0
fatigue / Early / 0.5-2.0
headache / Early / 0.5-2.0
insomnia / Early / 0.5-2.0
paresthesias / Delayed / 0.5-2.0
dizziness / Early / 0.5-2.0
malaise / Early / 0.5-2.0
alopecia / Delayed / 0.5-2.0
polyuria / Early / 0.1-0.2
increased urinary frequency / Early / 0.1-0.2
weight loss / Delayed / Incidence not known
dyspepsia / Early / Incidence not known
syncope / Early / Incidence not known
rhinitis / Early / Incidence not known
fever / Early / Incidence not known
photosensitivity / Delayed / Incidence not known
myalgia / Early / Incidence not known
leukocytosis / Delayed / Incidence not known
arthralgia / Delayed / Incidence not known
drowsiness / Early / Incidence not known
gynecomastia / Delayed / Incidence not known
asthenia / Delayed / Incidence not known

Boxed Warning
Neonates, pregnancy

When used during human pregnancy during the second and third trimesters, captopril, like other angiotensin-converting enzyme (ACE) inhibitors, can cause injury and even death to the developing fetus. When pregnancy is detected, captopril should be discontinued as soon as possible. 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. 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 babies exposed to ACE inhibitors during the first trimester, in those exposed to other antihypertensives during the first trimester, and in those whose mothers were hypertensive but were not treated. Newborns 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. Closely observe neonates with histories of in utero exposure to captopril for hypotension, oliguria, and hyperkalemia. If oliguria or hypotension occurs, blood pressure and renal perfusion support may be required, as well as exchange transfusion or dialysis to reverse hypotension and/or support decreased renal function.

Common Brand Names

Capoten

Dea Class

Rx

Description

Shortest acting, oral ACE inhibitor; contains a sulfhydryl group; side effects increase at higher doses; may be used for HTN, CHF, and various renal syndromes (e.g., diabetic nephropathy, proteinuria, scleroderma renal crisis).

Dosage And Indications
For the treatment of hypertension. Oral dosage Adults

25 mg PO 2 to 3 times daily, initially. May increase dose to 50 mg PO 3 times daily after 1 to 2 weeks or 24 hours or less under continuous medical supervision, followed by 100 mg PO 2 to 3 times daily and 150 mg PO 2 to 3 times daily if further control is needed. Usual dose range: 12.5 to 150 mg/day in 2 to 3 divided doses. Max: 450 mg/day.

Children† and Adolescents†

0.5 mg/kg/dose (Max: 25 mg/dose) PO 3 times daily, initially. May increase dose if further control is needed. Max: 6 mg/kg/day (up to 450 mg/day).

Infants†

0.05 mg/kg/dose PO 1 to 4 times daily, initially. May increase dose if further control is needed. Max: 6 mg/kg/day. 0.05 to 0.3 mg/kg PO every 8 to 24 hours titrated to clinical response (Max: 2 mg/kg/dose and 6 mg/kg/day) has been recommended based on a study of captopril in 73 pediatric patients (age: 11 days to 15 years). A lower initial dose, slower dose titration, and close monitoring of blood pressure response is necessary, especially in infants younger than 2 months.

Neonates†

0.01 to 0.1 mg/kg/dose PO every 8 to 24 hours, initially. May increase dose up to 0.5 mg/kg/dose PO every 6 to 24 hours if further control is needed. A lower initial dose, slower dose titration, and close monitoring of blood pressure response is necessary in neonatal patients due to the potential for a prolonged duration of action.

For the treatment of heart failure. Oral dosage Adults

6.25 mg PO 3 times daily, initially. Increase the dose as tolerated up to 50 mg PO 3 times daily. Most patients will have a satisfactory clinical improvement at 50 to 100 mg PO 3 times daily. When possible, delay any further increases in dosages above 50 mg PO 3 times daily for at least 2 weeks to determine is satisfactory response occurs. Max: 450 mg/day. Guidelines recommend an angiotensin-converting enzyme (ACE) inhibitor in combination with an evidence-based beta blocker and aldosterone antagonist, in select patients, for patients with chronic reduced ejection fraction heart failure (HFrEF) NYHA class I to IV to reduce morbidity and mortality. In patients with prior or current symptoms of chronic HFrEF, use of an ACE inhibitor is recommended. Continued use of an ACE inhibitor is recommended for all classes of HFrEF for those patients for whom subsequent angiotensin receptor-neprilysin inhibitor (ARNI) use is inappropriate. Use of an ACE inhibitor in patients with preserved ejection fraction heart failure (HFpEF) and hypertension is reasonable to control blood pressure.

Adolescents†

6.25 to 12.5 mg PO every 8 to 12 hours, initially. Increase the dose as tolerated. Usual Max: 150 mg/day.

Children†

0.1 to 2 mg/kg/dose (Max: 6.25 to 25 mg/dose) PO every 6 to 12 hours, initially. Increase the dose as tolerated. Max: 6 mg/kg/day. Usual Max: 150 mg/day. Initial doses are often lower than those used for hypertension (e.g., 0.3 mg/kg/dose).

Infants†

0.01 to 0.18 mg/kg/dose PO every 8 hours, initially. Increase the dose as tolerated. Dose range: 0.2 to 2.5 mg/kg/day. Some experts recommend a lower maximum dose of 1.5 mg/kg/day PO due to concern for increased adverse effects at higher doses.

Neonates†

0.01 to 0.03 mg/kg/dose PO every 8 hours, initially. Increase the dose as tolerated. Max: 1.5 mg/kg/day.

For the treatment of left ventricular dysfunction postmyocardial infarction. Oral dosage Adults

6.25 to 12.5 mg PO 3 times daily, initially. Increase the dose to 25 mg PO 3 times daily over the next several days and then 50 mg PO 3 times daily over the next several weeks.

For the treatment of hypertensive urgency† or hypertensive emergency†. Oral dosage Adults

25 mg PO, may repeat every 30 minutes as needed.

Geriatric

Initiate therapy at the lower end of the adult dosage range. Greater sensitivity to the usual adult dose is possible. Adjust dosage based on clinical response.

For the treatment of hypertension and the subsequent decline in renal function associated with scleroderma renal crisis (SRC)†. Oral dosage Adults

No specific dosage guidelines are available. Results of a study published in 1990 revealed the efficacy of ACE inhibitors in slowing the decline of renal function in systemic sclerosis; however, no dosage range was provided.

For the treatment of proteinuria associated with diabetic nephropathy or nephrotic syndrome†. For the treatment of proteinuria associated with diabetic nephropathy. Oral dosage Adults

12.5 to 25 mg PO 2 to 3 times daily, initially. Adjust dose based on blood pressure and serum creatinine and potassium concentrations every 2 to 4 weeks up to the maximum tolerated dose. Usual dose: 50 mg PO 3 times daily. Max: 450 mg/day in 2 or 3 divided doses.  The FDA-approved dosage is 25 mg PO 3 times daily.

Children† and Adolescents†

Initial doses of 0.3 to 1 mg/kg/dose PO 3 times daily titrated to clinical response up to a maximum dose of 6 mg/kg/day (administered in 3 divided doses) have been successful in reducing proteinuria or microalbuminuria in small studies (n = 8 to 15) of patients with diabetes or nephrotic syndrome unresponsive to conventional therapy. Although a specific total mg maximum dose has not been clearly defined, do not exceed initial and final doses recommended for adult patients (e.g., 25 mg/dose for initial doses and usual maximum of 150 mg/day for the final dose).

For the treatment of proteinuria associated with congenital nephrotic syndrome† or nephrotic syndrome†. Oral dosage Children and Adolescents

Initial doses of 0.3 to 1 mg/kg/dose PO 3 times daily titrated to clinical response up to a maximum dose of 6 mg/kg/day (administered in 3 divided doses) have been successful in reducing proteinuria or microalbuminuria in small studies (n = 8 to 15) of patients with diabetes or nephrotic syndrome unresponsive to conventional therapy. Although a specific total mg maximum dose has not been clearly defined, do not exceed initial and final doses recommended for adult patients (e.g., 25 mg/dose for initial doses and usual maximum of 150 mg/day for the final dose).

Neonates and Infants

Initial doses of 0.1 to 0.25 mg/kg/dose PO every 8 hours titrated to clinical response (Max: 6 mg/kg/day) have been used in combination with indomethacin (0.3 to 3 mg/kg/day PO divided every 12 hours) and unilateral nephrectomy in a small observational study (n = 7) of patients with congenital nephrotic syndrome. Treatment resulted in statistically significant increases in plasma albumin and decreases in albumin infusions over the follow-up period of 36 to 88 months.

†Indicates off-label use

Dosing Considerations
Hepatic Impairment

No dosage adjustments are recommended for captopril in hepatic impairment.

Renal Impairment

CrCl more than 50 mL/minute: no dosage adjustment needed.
CrCl 10 to 50 mL/minute: reduce recommended dose by 25%.
CrCl less than 10 mL/minute: reduce recommended dose by 50%.
 
Intermittent hemodialysis
Captopril is significantly removed by dialysis; doses should be given after dialysis. For pediatric patients, an initial dose reduction of 50% is recommended. Evaluate and adjust dosage of captopril based on clinical response to therapy.
 
Peritoneal dialysis
Adult patients: Reduce the initial dose by 25%, then titrate to desired clinical effect.
Pediatric patients: Reduce the initial dose by 50%, then titrate to desired clinical effect.
 
Continuous renal replacement therapy (CRRT)
Reduce the initial dose by 25%, then titrate to desired clinical effect.

Drug Interactions

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.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (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.
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.
Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (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.
Acetaminophen; Dextromethorphan; Pseudoephedrine: (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.
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.
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.
Acetaminophen; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Acrivastine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Aldesleukin, IL-2: (Moderate) Angiotensin converting enzyme inhibitors, like other antihypertensive agents, 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.
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.
Alogliptin; Metformin: (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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Aripiprazole: (Minor) Aripiprazole may enhance the hypotensive effects of antihypertensive agents.
Articaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral 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.
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.
Benzphetamine: (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.
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.
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.
Brompheniramine; Pseudoephedrine: (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) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Bupivacaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
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.
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.
Calcium; Vitamin D: (Major) Antacids can decrease the GI absorption of captopril if administered simultaneously.
Canagliflozin; Metformin: (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.
Carbidopa; Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
Carbidopa; Levodopa; Entacapone: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
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.
Cetirizine; Pseudoephedrine: (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) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Chloroprocaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
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.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (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) 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.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (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.
Chlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
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; Guaifenesin; Pseudoephedrine: (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) 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.
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.
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.
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; Metformin: (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.
Desloratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Dexbrompheniramine; Pseudoephedrine: (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) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
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.
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.
Dextromethorphan; Guaifenesin; Pseudoephedrine: (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.
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.
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.
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.
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.
Duloxetine: (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; Linagliptin; Metformin: (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.
Empagliflozin; Metformin: (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.
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.
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.
Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral 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) 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.
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.
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.
Etomidate: (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.
Fexofenadine; Pseudoephedrine: (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.
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.
General anesthetics: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Glipizide; Metformin: (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.
Glyburide; Metformin: (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.
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.
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.
Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Haloperidol: (Moderate) In general, haloperidol should be used cautiously with antihypertensive agents due to the possibility of additive hypotension.
Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
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; Pseudoephedrine: (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.
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.
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.
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.
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.
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.
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.
Isoflurane: (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.
Isosorbide Mononitrate: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
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.
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.
Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
Lidocaine; Epinephrine: (Moderate) Antihypertensives, including angiotensin-converting enzyme inhibitors, antagonize the vasopressor effects of parenteral epinephrine.
Linagliptin; Metformin: (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.
Lisdexamfetamine: (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.
Lithium: (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.
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.
Loratadine; Pseudoephedrine: (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.
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.
Metformin: (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) 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; Rosiglitazone: (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; Saxagliptin: (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; Sitagliptin: (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.
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.
Methohexital: (Moderate) Concurrent use of methohexital and antihypertensive agents increases the risk of developing hypotension.
Methylphenidate Derivatives: (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.
Milrinone: (Moderate) Concurrent administration of antihypertensive agents could lead to additive hypotension when administered with milrinone. Titrate milrinone dosage according to hemodynamic response.
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; Pseudoephedrine: (Moderate) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Nateglini

de: (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.
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.
Nesiritide, BNP: (Major) The potential for hypotension may be increased when coadministering nesiritide with antihypertensive agents.
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.
Nitroglycerin: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
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: (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.
Olanzapine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
Olanzapine; Fluoxetine: (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.
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.
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.
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.
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.
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.
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.
Pioglitazone; Metformin: (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.
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.
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.
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.
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.
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.
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.
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.
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.
Propofol: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
Pseudoephedrine: (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) The cardiovascular effects of pseudoephedrine may reduce the antihypertensive effects produced by angiotensin-converting enzyme inhibitors. Monitor heart rate and blood pressure.
Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
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.
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.
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.
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.
Sevoflurane: (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.
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.
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.
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.
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).
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.
Sulfamethoxazole; Trimethoprim, SMX-TMP, Cotrimoxazole: (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.
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.
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.
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.
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.
Thiazide 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.
Thiothixene: (Moderate) Thiothixene should be used cautiously in patients receiving antihypertensive agents. Additive hypotensive effects are possible.
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.
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.
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.
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.
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.
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.
Ziprasidone: (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

Capoten/Captopril Oral Tab: 12.5mg, 25mg, 50mg, 100mg

Maximum Dosage
Adults

450 mg/day PO.

Geriatric

450 mg/day PO.

Adolescents

Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO (Max: 450 mg/day) have been used off-label.

Children

Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO (Max: 450 mg/day) have been used off-label.

Infants

Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO have been used off-label. A lower maximum of 1.5 mg/kg/day PO is recommended for congestive heart failure.

Neonates

Safety and efficacy have not been established; however, doses up to 6 mg/kg/day PO have been used off-label. A lower maximum of 1.5 mg/kg/day PO is recommended for congestive heart failure.

Mechanism Of Action

Captopril has a high affinity for ACE and competes with angiotensin I, the natural substrate, to block its conversion to angiotensin II. Angiotensin II is a potent vasoconstrictor and a negative feedback mediator for renin activity. Thus, as a result of lower angiotensin II plasma levels, blood pressure decreases and plasma renin activity increases. In addition, baroreceptor reflex mechanisms are stimulated by the drop in blood pressure. Kininase II, identical to ACE, is an enzyme that degrades 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.
 
The "local" activity of ACE inhibitors may be more responsible for their clinical effects than systemic activity. ACE-inhibiting drugs may act locally (i.e., within a specific tissue) to reduce vascular tone by decreasing local angiotensin II-induced sympathetic activity and/or by decreasing local angiotensin II-induced vasoconstrictive activity. ACE inhibitors may inhibit presynaptic norepinephrine release and postsynaptic adrenergic receptor activity, decreasing vascular sensitivity to vasopressor activity. Decreases in plasma angiotensin II levels reduce aldosterone secretion, with a subsequent decrease in 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. However, captopril can increase cardiac output, cardiac index, stroke volume, and exercise tolerance in patients with congestive heart failure. The drug also decreases pulmonary wedge pressure, pulmonary vascular resistance, and mean arterial and right atrial pressures in these patients. As antihypertensives, ACE inhibitors reduce LVH, do not worsen insulin resistance or hyperlipidemia, and do not cause sexual dysfunction.

Pharmacokinetics

Captopril is administered orally. Captopril distributes into most body tissues, and approximately 25% is bound to 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.
 
Affected cytochrome P450 isoenzymes and drug transporters: P-glycoprotein (P-gp)
Captopril is an inhibitor of P-gp and may increase the plasma concentrations of drugs that are substrates of P-gp.

Oral Route

After oral administration, captopril is rapidly absorbed from the GI tract. If given with food, absorption decreases by 30% to 40%. Noticeable antihypertensive effects begin within 15 minutes; maximum beneficial effects require several weeks of therapy. The effects of a dose of captopril generally last about 2 to 6 hours, but the duration of action can be prolonged in patients with renal dysfunction.

Pregnancy And Lactation
Pregnancy

Concentrations of captopril in human milk are about 1% of those in maternal blood. Due to low levels in breast milk, guidelines generally consider captopril and enalapril to be compatible with breast-feeding unless high doses are required. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition.