Synercid

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Synercid

Classes

Streptogramin Antibiotics

Administration
Injectable Administration

Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.

Intravenous Administration

Reconstitution
Reconstitute the 500 mg single dose vial by slowly adding 5 mL of 5% Dextrose for injection or sterile water for injection to a concentration of 100 mg/mL.
Gently swirl the vial by manual rotation without shaking to ensure dissolution of contents.
Allow the solution to sit for a few minutes until all of the foam has disappear. The resulting solutions should be clear.
Storage after reconstitution: The reconstituted solution should be diluted within 30 minutes.
Dilution
Add the appropriate dose of the reconstituted solution to 250 mL of 5% Dextrose for injection for peripheral administration. An infusion volume of 100 mL may be used for central line administrations.
If venous irritation occurs with peripheral administration using 250 mL, consider increasing the infusion volume to 500—100 mL, changing the infusion site, or infusing via a peripherally inserted central catheter (PICC) or a central line.
Storage after dilution: The diluted solution is stable for 5 hours at room temperature or for 54 hours refrigerated (2—8 degrees C or 36—46 degrees F). Do not freeze.
Intravenous infusion
Infuse over 60 minutes.
An infusion pump or device may be used to control the rate of infusion.

Adverse Reactions
Severe

thrombosis / Delayed / 1.7-1.7
pancreatitis / Delayed / 0-1.0
anaphylactic shock / Rapid / 0-1.0
angioedema / Rapid / 0-1.0
pleural effusion / Delayed / 0-1.0
GI bleeding / Delayed / 0-0.2
anaphylactoid reactions / Rapid / 0-0.1
seizures / Delayed / 0-0.1
ventricular fibrillation / Early / 0-0.1
pericarditis / Delayed / 0-0.1
pericardial effusion / Delayed / 0-0.1
acute respiratory distress syndrome (ARDS) / Early / 0-0.1
apnea / Delayed / 0-0.1
hemolytic anemia / Delayed / 0-0.1
pancytopenia / Delayed / 0-0.1
stroke / Early / 0-0.1
C. difficile-associated diarrhea / Delayed / Incidence not known

Moderate

hyperbilirubinemia / Delayed / 25.0-34.6
edema / Delayed / 17.3-18.0
phlebitis / Rapid / 0-2.4
elevated hepatic enzymes / Delayed / 0.4-1.9
stomatitis / Delayed / 0-1.0
constipation / Delayed / 0-1.0
myasthenia / Delayed / 0-1.0
pseudomembranous colitis / Delayed / 0-1.0
peripheral vasodilation / Rapid / 0-1.0
hypertonia / Delayed / 0-1.0
confusion / Early / 0-1.0
chest pain (unspecified) / Early / 0-1.0
palpitations / Early / 0-1.0
peripheral edema / Delayed / 0-1.0
gout / Delayed / 0-1.0
dyspnea / Early / 0-1.0
hematuria / Delayed / 0-1.0
hypotension / Rapid / 0-0.2
bone pain / Delayed / 0-0.1
jaundice / Delayed / 0-0.1
hepatitis / Delayed / 0-0.1
skin ulcer / Delayed / 0-0.1
peripheral neuropathy / Delayed / 0-0.1
encephalopathy / Delayed / 0-0.1
hypovolemia / Early / 0-0.1
supraventricular tachycardia (SVT) / Early / 0-0.1
hypoventilation / Rapid / 0-0.1
hypoxia / Early / 0-0.1
hemolysis / Early / 0-0.1
hypoglycemia / Early / 0-0.1
hyponatremia / Delayed / 0-0.1
superinfection / Delayed / Incidence not known
vaginitis / Delayed / Incidence not known
candidiasis / Delayed / Incidence not known

Mild

injection site reaction / Rapid / 11.6-42.0
arthralgia / Delayed / 0-7.8
myalgia / Early / 0-6.8
nausea / Early / 2.8-4.9
vomiting / Early / 2.7-3.7
rash / Early / 2.5-3.1
diarrhea / Early / 2.7-2.7
headache / Early / 1.6-1.6
pruritus / Rapid / 1.5-1.5
abdominal pain / Early / 0-1.0
dyspepsia / Early / 0-1.0
maculopapular rash / Early / 0-1.0
hyperhidrosis / Delayed / 0-1.0
urticaria / Rapid / 0-1.0
insomnia / Early / 0-1.0
dizziness / Early / 0-1.0
anxiety / Delayed / 0-1.0
paresthesias / Delayed / 0-1.0
fever / Early / 0-1.0
syncope / Early / 0-0.1
tremor / Early / 0-0.1

Common Brand Names

Synercid

Dea Class

Rx

Description

Streptogramin antibiotics isolated from Streptomyces pristinaespiralis. They act synergistically against susceptible bacteria when administered together. The combination has up to 16 times the activity of each agent alone. Used for vancomycin-resistant Enterococcus faecium bacteremia and for complicated skin and skin-structure infections due to Staphylococcus aureus.

Dosage And Indications
For the treatment of complicated skin and skin structure infections. For the treatment of unspecified complicated skin and skin structure infections. Intravenous dosage Adults

7.5 mg/kg/dose IV every 12 hours for at least 7 days.

Children and Adolescents 12 to 17 years

7.5 mg/kg/dose IV every 12 hours for at least 7 days.

Infants† and Children 1 to 11 years†

7.5 mg/kg/dose IV every 12 hours.

For the treatment of necrotizing infections of the skin, fascia, and muscle. Intravenous dosage Adults

7.5 mg/kg/dose IV every 12 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours as an alternative for necrotizing infections due to S. aureus or Streptococcus in patients with severe penicillin hypersensitivity.

Children and Adolescents 12 to 17 years

7.5 mg/kg/dose IV every 12 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours as an alternative for necrotizing infections due to S. aureus or Streptococcus in patients with severe penicillin hypersensitivity.

Infants† and Children 1 to 11 years†

7.5 mg/kg/dose IV every 12 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours as an alternative for necrotizing infections due to S. aureus or Streptococcus in patients with severe penicillin hypersensitivity. 

For the treatment of serious or life-threatening infections such as bacteremia†. Intravenous dosage Adults

7.5 mg/kg/dose IV every 8 hours. Clinical practice guidelines suggest dalfopristin; quinupristin as an option in patients with persistent MRSA bacteremia that has reduced susceptibilities to vancomycin and daptomycin. 7.5 mg/kg/dose IV every 8 hours was used for the global dalfopristin; quinupristin emergency-use program (n = 90) in a multicenter, open-label, noncomparator study. The clinical success rate was 75.6% and the overall success rate was 71.1% in all-treated patients. The clinical success rate was 74.1% and the overall success rate was 66.7% in the clinically and bacteriologically evaluable patients. One retrospective study (n = 113) suggested that while efficacy was similar between study groups, prolonged bacteremia and resistance development was more common with dalfopristin; quinupristin than with linezolid. Dalfopristin; quinupristin will not treat E. faecalis.

Infants, Children, and Adolescents

7.5 mg/kg/dose IV every 8 hours. Clinical practice guidelines suggest dalfopristin; quinupristin as an option in adult patients with persistent MRSA bacteremia that has reduced susceptibilities to vancomycin and daptomycin; however, pediatric-specific recommendations are not available. Pediatric patients treated with dalfopristin; quinupristin in a global emergency-use program (n = 131) had a mean age of 7.3 years (range 0.1 to 17.8 years) and were treated for bacteremia, intra-abdominal infections, respiratory tract infections, bone and joint infections, UTIs, endocarditis, and other infections. Other case reports include treatment for a shunt infection as well as immunosuppressed patients, including organ and stem-cell transplant patients. Dalfopristin; quinupristin will not treat E. faecalis.

For the treatment of peritoneal dialysis-related peritonitis†. Intermittent Intraperitoneal dosage† Adults

25 mg/L intraperitoneally in alternate exchanges for 21 days in combination with IV therapy.

Intravenous dosage Adults

500 mg IV every 12 hours for 21 days in combination with intraperitoneal therapy.

†Indicates off-label use

Dosing Considerations
Hepatic Impairment

Dosage reduction may be necessary; however, specific guidelines are not available.

Renal Impairment

No dosage adjustment necessary. In patients with creatine clearance 6—28 mL/min, the AUC of dalfopristin and quinupristin in combination with their major metabolites increased about 30% and 40%, respectively.
 
Intermittent hemodialysis
Dalfopristin; quinupristin is not removed by hemodialysis; no dosage adjustment is required in renal impairment.
 
Peritoneal dialysis
No dosage adjustment are necessary for CAPD. The clearance of dalfopristin, quinupristin, and their metabolites is negligible in patients undergoing CAPD.

Drug Interactions

Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) Concomitant use of dihydrocodeine with dalfopristin; quinupristin may increase dihydrocodeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased dihydromorphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when dihydrocodeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of dihydrocodeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease dihydrocodeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to dihydrocodeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4, an isoenzyme partially responsible for the metabolism of dihydrocodeine.
Acetaminophen; Codeine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Acetaminophen; Hydrocodone: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Acetaminophen; Oxycodone: (Moderate) Consider a reduced dose of oxycodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the oxycodone dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Oxycodone is a CYP3A4 substrate, and coadministration with a weak inhibitor like dalfopristin; quinupristin can increase oxycodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of oxycodone. If dalfopristin; quinupristin is discontinued, oxycodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to oxycodone.
Alfentanil: (Moderate) Consider a reduced dose of alfentanil with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the alfentanil dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Alfentanil is a sensitive CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase alfentanil exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of alfentanil. If dalfopristin; quinupristin is discontinued, alfentanil plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to alfentanil.
Almotriptan: (Major) Dalfopristin; quinupristin may increase the systemic exposure of almotriptan. If coadministered, the recommended starting dose of almotriptan is 6.25 mg; do not exceed 12.5 mg within a 24-hour period. Avoid coadministration in patients with renal or hepatic impairment. Almotriptan is a CYP3A4 substrate and quinupristin is a potent CYP3A4 inhibitor. In a drug interaction study, coadministration of almotriptan and ketoconazole, another potent CYP3A4 inhibitor, resulted in an approximately 60% increase in almotriptan exposure.
Alosetron: (Moderate) Dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including alosetron.
Alprazolam: (Major) Coadministration of alprazolam and dalfopristin; quinupristin is not recommended. If coadministration cannot be avoided, a dosage reduction of alprazolam should be considered. Dalfopristin; quinupristin is a potent CYP3A4 inhibitor. The initial step in alprazolam metabolism is hydroxylation catalyzed by cytochrome CYP3A. Drugs that inhibit this metabolic pathway may profoundly decrease alprazolam clearance, resulting in increased potential for serious alprazolam-related adverse events, such as respiratory depression and prolonged sedation. Consequently, alprazolam should be avoided in patients receiving very potent inhibitors of CYP3A isoenzymes.
Amlodipine; Atorvastatin: (Moderate) Dalfopristin; quinupristin has been shown to inhibit CYP3A4 and may decrease the elimination of atorvastatin, a CYP3A4 substrate.
Aripiprazole: (Moderate) Monitor for aripiprazole-related adverse reactions during concomitant use of quinupristin. Patients receiving both a CYP2D6 inhibitor plus quinupristin may require an aripiprazole dosage adjustment. Dosing recommendations vary based on aripiprazole dosage form, CYP2D6 inhibitor strength, and CYP2D6 metabolizer status. See prescribing information for details. Concomitant use may increase aripiprazole exposure and risk for side effects. Aripiprazole is a CYP3A and CYP2D6 substrate; quinupristin is a weak CYP3A inhibitor.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Aspirin, ASA; Oxycodone: (Moderate) Consider a reduced dose of oxycodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the oxycodone dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Oxycodone is a CYP3A4 substrate, and coadministration with a weak inhibitor like dalfopristin; quinupristin can increase oxycodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of oxycodone. If dalfopristin; quinupristin is discontinued, oxycodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to oxycodone.
Atazanavir; Cobicistat: (Moderate) Caution is warranted when cobicistat is administered with dalfopristin; quinupristin as there is a potential for elevated cobicistat concentrations. Quinupristin is a CYP3A4 inhibitor and cobicistat is substrate of CYP3A4.
Atorvastatin: (Moderate) Dalfopristin; quinupristin has been shown to inhibit CYP3A4 and may decrease the elimination of atorvastatin, a CYP3A4 substrate.
Atorvastatin; Ezetimibe: (Moderate) Dalfopristin; quinupristin has been shown to inhibit CYP3A4 and may decrease the elimination of atorvastatin, a CYP3A4 substrate.
Benzhydrocodone; Acetaminophen: (Moderate) Concurrent use of benzhydrocodone with dalfopristin; quinupristin may increase the risk of increased opioid-related adverse reactions, such as fatal respiratory depression. Consider a dose reduction of benzhydrocodone until stable drug effects are achieved. Monitor patients for respiratory depression and sedation at frequent intervals. Discontinuation of dalfopristin; quinupristin in a patient taking benzhydrocodone may decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to opioid agonists. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Benzhydrocodone is a prodrug for hydrocodone. Hydrocodone is a substrate for CYP3A4. Quinupristin is a strong inhibitor of CYP3A4.
Bupivacaine; Lidocaine: (Moderate) Coadministration of lidocaine with dalfopristin; quinupristin may result in elevated lidocaine plasma concentrations. If these drugs are used together, closely monitor for signs of lidocaine-related adverse events. Lidocaine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Buprenorphine: (Moderate) Concomitant use of buprenorphine and dalfopristin; quinupristin can increase the plasma concentration of buprenorphine, resulting in increased or prolonged opioid effects, particularly when dalfopristin; quinupristin is added after a stable buprenorphine dose is achieved. If concurrent use is necessary, consider dosage reduction of buprenorphine until stable drug effects are achieved. Monitor patient for respiratory depression and sedation at frequent intervals. When stopping dalfopristin; quinupristin, the buprenorphine concentration may decrease, potentially resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependency. If dalfopristin; quinupristin is discontinued, consider increasing buprenorphine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. Buprenorphine is a substrate of CYP3A4. Dalfopristin; quinupristin is a CYP3A4 inhibitor.
Buprenorphine; Naloxone: (Moderate) Concomitant use of buprenorphine and dalfopristin; quinupristin can increase the plasma concentration of buprenorphine, resulting in increased or prolonged opioid effects, particularly when dalfopristin; quinupristin is added after a stable buprenorphine dose is achieved. If concurrent use is necessary, consider dosage reduction of buprenorphine until stable drug effects are achieved. Monitor patient for respiratory depression and sedation at frequent intervals. When stopping dalfopristin; quinupristin, the buprenorphine concentration may decrease, potentially resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependency. If dalfopristin; quinupristin is discontinued, consider increasing buprenorphine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. Buprenorphine is a substrate of CYP3A4. Dalfopristin; quinupristin is a CYP3A4 inhibitor.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Carbamazepine: (Moderate) Dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including carbamazepine.
Chlorpheniramine; Codeine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) Concomitant use of dihydrocodeine with dalfopristin; quinupristin may increase dihydrocodeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased dihydromorphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when dihydrocodeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of dihydrocodeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease dihydrocodeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to dihydrocodeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4, an isoenzyme partially responsible for the metabolism of dihydrocodeine.
Chlorpheniramine; Hydrocodone: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Cisapride: (Contraindicated) Post-marketing surveillance reports have documented QT prolongation and ventricular arrhythmias, including torsade de pointes and death, when known and potent inhibitors of CYP3A4 are coadministered with cisapride. Dalfopristin; quinupristin may have the potential to inhibit the metabolism of cisapride through CYP3A4 and thus, should not be used with cisapride.
Clozapine: (Moderate) Consider a clozapine dose reduction if coadministered with dalfopristin; quinupristin and monitor for adverse reactions. If dalfopristin; quinupristin is discontinued, monitor for lack of clozapine effect and increase dose if necessary. A clinically relevant increase in the plasma concentration of clozapine may occur during concurrent use. Clozapine is partially metabolized by CYP3A4. Dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Cobicistat: (Moderate) Caution is warranted when cobicistat is administered with dalfopristin; quinupristin as there is a potential for elevated cobicistat concentrations. Quinupristin is a CYP3A4 inhibitor and cobicistat is substrate of CYP3A4.
Codeine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Codeine; Guaifenesin: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Codeine; Phenylephrine; Promethazine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Codeine; Promethazine: (Moderate) Concomitant use of codeine with dalfopristin; quinupristin may increase codeine plasma concentrations, resulting in greater metabolism by CYP2D6, increased morphine concentrations, and prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when codeine is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of codeine until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease codeine plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to codeine. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Codeine is primarily metabolized by CYP2D6 to morphine, and by CYP3A4 to norcodeine; norcodeine does not have analgesic properties. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Conjugated Estrogens: (Minor) Estrogens are partially metabolized by CYP3A4. Drugs that inhibit CYP3A4 such as dalfopristin; quinupristin may increase plasma concentrations of estrogens and cause estrogen-related side effects such as nausea and breast tenderness. Patients receiving estrogens should be monitored for an increase in adverse events.
Conjugated Estrogens; Bazedoxifene: (Minor) Estrogens are partially metabolized by CYP3A4. Drugs that inhibit CYP3A4 such as dalfopristin; quinupristin may increase plasma concentrations of estrogens and cause estrogen-related side effects such as nausea and breast tenderness. Patients receiving estrogens should be monitored for an increase in adverse events.
Conjugated Estrogens; Medroxyprogesterone: (Minor) Estrogens are partially metabolized by CYP3A4. Drugs that inhibit CYP3A4 such as dalfopristin; quinupristin may increase plasma concentrations of estrogens and cause estrogen-related side effects such as nausea and breast tenderness. Patients receiving estrogens should be monitored for an increase in adverse events.
Cyclosporine: (Moderate) Cyclosporine therapeutic drug monitoring is recommended when administered concurrently with dalfopristin; quinupristin. Use of these medications together resulted in a 63% increase in exposure of cyclosporine, which may increase the risk for cyclosporine-related toxicity. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4 and cyclosporine is a CYP3A4 substrate.
Dapagliflozin; Saxagliptin: (Major) The manufacturer recommends limiting the saxagliptin dose to 2.5 mg/day if used with strong CYP3A4/5 inhibitors such as dalfopristin; quinupristin. The metabolism of saxagliptin is primarily mediated by CYP3A4/5, and maximum serum concentrations and exposure of saxagliptin are increased when administered with strong inhibitors. Monitor patients for hypoglycemia if these drugs are used together.
Darunavir: (Moderate) Caution is warranted when darunavir is administered with dalfopristin; quinupristin as there is a potential for elevated concentrations of darunavir. Quinupristin is a CYP3A4 inhibitor; darunavir is a substrate of CYP3A4.
Darunavir; Cobicistat: (Moderate) Caution is warranted when cobicistat is administered with dalfopristin; quinupristin as there is a potential for elevated cobicistat concentrations. Quinupristin is a CYP3A4 inhibitor and cobicistat is substrate of CYP3A4. (Moderate) Caution is warranted when darunavir is administered with dalfopristin; quinupristin as there is a potential for elevated concentrations of darunavir. Quinupristin is a CYP3A4 inhibitor; darunavir is a substrate of CYP3A4.
Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: (Moderate) Caution is warranted when cobicistat is administered with dalfopristin; quinupristin as there is a potential for elevated cobicistat concentrations. Quinupristin is a CYP3A4 inhibitor and cobicistat is substrate of CYP3A4. (Moderate) Caution is warranted when darunavir is administered with dalfopristin; quinupristin as there is a potential for elevated concentrations of darunavir. Quinupristin is a CYP3A4 inhibitor; darunavir is a substrate of CYP3A4.
Desogestrel; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Dextromethorphan; Quinidine: (Moderate) Coadministration of quinidine with dalfopristin; quinupristin may result in elevated quinidine plasma concentrations. If these drugs are used together, closely monitor for signs of quinidine-related adverse events. Quinidine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Diazepam: (Moderate) Monitor for diazepam-related adverse reactions including sedation and respiratory depression if coadministration with dalfopristin; quinupristin is necessary due to increased diazepam exposure. Dalfopristin; quinupristin is a weak CYP3A4 inhibitor and diazepam is metabolized by CYP3A4.
Dienogest; Estradiol valerate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Disopyramide: (Moderate) Caution is warranted during coadministration of disopyramide and dalfopristin; quinupristin due to the potential for elevated disopyramide plasma concentrations and associated adverse events including QT prolongation. Disopyramide is a CYP3A4 substrate; dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Docetaxel: (Moderate) Caution is warranted during coadministration of docetaxel and dalfopristin; quinupristin, as the systemic exposure of docetaxel may be increased resulting in increased treatment-related adverse reactions. Docetaxel is a CYP3A4 substrate; dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Dofetilide: (Moderate) Monitor for an increase in dofetilide-related adverse reactions, including QT prolongation, if coadministration with dalfopristin; quinupristin is necessary. Dalfopristin; quinupristin is a weak CYP3A4 inhibitor. Dofetilide is a minor CYP3A4 substrate; however, because there is a linear relationship between dofetilide plasma concentration and QTc, concomitant administration of CYP3A4 inhibitors may increase the risk of arrhythmia (torsade de pointes).
Doxorubicin Liposomal: (Major) Avoid coadministration of dalfopristin; quinupristin with doxorubicin due to increased systemic exposure of doxorubicin resulting in increased treatment-related adverse reactions. Dalfopristin; quinupristin is a weak CYP3A4 inhibitor and doxorubicin is a major substrate of CYP3A4. Concurrent use of CYP3A4 inhibitors with doxorubicin has resulted in clinically significant interactions.
Doxorubicin: (Major) Avoid coadministration of dalfopristin; quinupristin with doxorubicin due to increased systemic exposure of doxorubicin resulting in increased treatment-related adverse reactions. Dalfopristin; quinupristin is a weak CYP3A4 inhibitor and doxorubicin is a major substrate of CYP3A4. Concurrent use of CYP3A4 inhibitors with doxorubicin has resulted in clinically significant interactions.
Drospirenone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Drospirenone; Estetrol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Drospirenone; Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Drospirenone; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Drospirenone; Ethinyl Estradiol; Levomefolate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Elagolix; Estradiol; Norethindrone acetate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Eliglustat: (Major) In poor CYP2D6 metabolizers (PMs), coadministration of dalfopristin; quinupristin and eliglustat is not recommended. In extensive CYP2D6 metabolizers (EM) with mild hepatic impairment, coadministration of these agents requires dosage reduction of eliglustat to 84 mg PO once daily. Dalfopristin; quinupristin is a weak CYP3A inhibitor; eliglustat is a CYP3A and CYP2D6 substrate. Because CYP3A plays a significant role in the metabolism of eliglustat in CYP2D6 PMs, coadministration with CYP3A inhibitors may increase eliglustat exposure and the risk of serious adverse events (e.g., QT prolongation and cardiac arrhythmias) in these patients.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide: (Moderate) Caution is warranted when cobicistat is administered with dalfopristin; quinupristin as there is a potential for elevated cobicistat concentrations. Quinupristin is a CYP3A4 inhibitor and cobicistat is substrate of CYP3A4. (Moderate) Caution is warranted when elvitegravir is administered with dalfopristin; quinupristin as there is a potential for elevated elvitegravir concentrations. Quinupristin is a CYP3A4 inhibitor and elvitegravir is a substrate of CYP3A4.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Caution is warranted when cobicistat is administered with dalfopristin; quinupristin as there is a potential for elevated cobicistat concentrations. Quinupristin is a CYP3A4 inhibitor and cobicistat is substrate of CYP3A4. (Moderate) Caution is warranted when elvitegravir is administered with dalfopristin; quinupristin as there is a potential for elevated elvitegravir concentrations. Quinupristin is a CYP3A4 inhibitor and elvitegravir is a substrate of CYP3A4.
Estradiol; Levonorgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Estradiol; Norethindrone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Estradiol; Norgestimate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Ethinyl Estradiol; Norelgestromin: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized

by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Ethinyl Estradiol; Norethindrone Acetate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Ethinyl Estradiol; Norgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Ethynodiol Diacetate; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Etonogestrel; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Felodipine: (Moderate) Coadministration of felodipine with dalfopristin; quinupristin may result in elevated felodipine plasma concentrations. If these drugs are used together, closely monitor for signs of felodipine-related adverse events. Felodipine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Fentanyl: (Moderate) Consider a reduced dose of fentanyl with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the fentanyl dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Fentanyl is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase fentanyl exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of fentanyl. If dalfopristin; quinupristin is discontinued, fentanyl plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to fentanyl.
Finerenone: (Moderate) Monitor serum potassium during initiation or dose adjustment of either finerenone or dalfopristin; quinupristin; a finerenone dosage reduction may be necessary. Concomitant use may increase finerenone exposure and the risk of hyperkalemia. Finerenone is a CYP3A substrate and dalfopristin; quinupristin is a weak CYP3A inhibitor. Coadministration with another weak CYP3A inhibitor increased overall exposure to finerenone by 21%.
Flibanserin: (Moderate) The concomitant use of flibanserin and multiple weak CYP3A4 inhibitors, including dalfopristin; quinupristin, may increase flibanserin concentrations, which may increase the risk of flibanserin-induced adverse reactions. Therefore, patients should be monitored for hypotension, syncope, somnolence, or other adverse reactions, and the potential outcomes of combination therapy with multiple weak CYP3A4 inhibitors and flibanserin should be discussed with the patient.
Guaifenesin; Hydrocodone: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Homatropine; Hydrocodone: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Hydrocodone: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Hydrocodone; Ibuprofen: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Hydrocodone; Pseudoephedrine: (Moderate) Consider a reduced dose of hydrocodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. Hydrocodone is a CYP3A4 substrate, and coadministration with CYP3A4 inhibitors like dalfopristin; quinupristin can increase hydrocodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of hydrocodone. These effects could be more pronounced in patients also receiving a CYP2D6 inhibitor. If dalfopristin; quinupristin is discontinued, hydrocodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to hydrocodone.
Ibuprofen; Oxycodone: (Moderate) Consider a reduced dose of oxycodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the oxycodone dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Oxycodone is a CYP3A4 substrate, and coadministration with a weak inhibitor like dalfopristin; quinupristin can increase oxycodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of oxycodone. If dalfopristin; quinupristin is discontinued, oxycodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to oxycodone.
Isradipine: (Minor) Coadministration of dalfopristin; quinupristin and isradipine may cause an increase in systemic concentrations of isradipine. Use caution when administering these drugs concomitantly. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4. Isradipine is a CYP3A4 substrate.
Ixabepilone: (Moderate) Monitor for ixabepilone toxicity and reduce the ixabepilone dose as needed if concurrent use of dalfopristin; quinupristin is necessary. Concomitant use may increase ixabepilone exposure and the risk of adverse reactions. Ixabepilone is a CYP3A substrate and dalfopristin; quinupristin is a weak CYP3A inhibitor.
Lemborexant: (Major) Limit the dose of lemborexant to a maximum of 5 mg PO once daily if coadministered with streptogramins such as quinupristin as concurrent use may increase lemborexant exposure and the risk of adverse effects. Lemborexant is a CYP3A4 substrate; quinupristin inhibits CYP3A4. It is reasonable to expect that the concomitant administration may likely result in increased plasma concentrations of lemborexant. Coadministration of lemborexant with a weak CYP3A4 inhibitor is predicted to increase lemborexant exposure by less than 2-fold.
Leuprolide; Norethindrone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Levonorgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Levonorgestrel; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Levonorgestrel; Ethinyl Estradiol; Ferrous Bisglycinate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Levonorgestrel; Ethinyl Estradiol; Ferrous Fumarate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Lidocaine: (Moderate) Coadministration of lidocaine with dalfopristin; quinupristin may result in elevated lidocaine plasma concentrations. If these drugs are used together, closely monitor for signs of lidocaine-related adverse events. Lidocaine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Lidocaine; Epinephrine: (Moderate) Coadministration of lidocaine with dalfopristin; quinupristin may result in elevated lidocaine plasma concentrations. If these drugs are used together, closely monitor for signs of lidocaine-related adverse events. Lidocaine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Lidocaine; Prilocaine: (Moderate) Coadministration of lidocaine with dalfopristin; quinupristin may result in elevated lidocaine plasma concentrations. If these drugs are used together, closely monitor for signs of lidocaine-related adverse events. Lidocaine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Lonafarnib: (Major) Avoid coadministration of lonafarnib and dalfopristin; quinupristin; concurrent use may increase the exposure of lonafarnib and the risk of adverse effects. If coadministration is unavoidable, reduce to or continue lonafarnib at a dosage of 115 mg/m2 and closely monitor patients for lonafarnib-related adverse reactions. Resume previous lonafarnib dosage 14 days after discontinuing dalfopristin; quinupristin. Lonafarnib is a sensitive CYP3A4 substrate and dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Metformin; Saxagliptin: (Major) The manufacturer recommends limiting the saxagliptin dose to 2.5 mg/day if used with strong CYP3A4/5 inhibitors such as dalfopristin; quinupristin. The metabolism of saxagliptin is primarily mediated by CYP3A4/5, and maximum serum concentrations and exposure of saxagliptin are increased when administered with strong inhibitors. Monitor patients for hypoglycemia if these drugs are used together.
Methadone: (Moderate) Concomitant use of methadone with dalfopristin; quinupristin may increase methadone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. Monitor patients closely at frequent intervals and consider a dosage reduction of methadone until stable drug effects are achieved. Discontinuation of dalfopristin; quinupristin could decrease methadone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to methadone. If dalfopristin; quinupristin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Methadone is a substrate for CYP3A4. Dalfopristin; quinupristin is a weak inhibitor of CYP3A4.
Methylergonovine: (Moderate) Be alert for symptoms of ergot toxicity if using methylergonovine and dalfopristin; quinupristin together is medically necessary. An ergot alkaloid dose reduction may be necessary if these drugs are used together. Concomitant use of dalfopristin; quinupristin, a weak CYP3A4 inhibitor, and methylergonovine, a CYP3A4 substrate, may result in increased ergot alkaloid levels.
Midazolam: (Moderate) Monitor for increased midazolam adverse effects if coadministered with dalfopristin; quinupristin. Concomitant administration of dalfopristin; quinupristin and midazolam (intravenous bolus dose) in healthy volunteers increased the midazolam AUC by 33%.
Nanoparticle Albumin-Bound Sirolimus: (Major) Reduce the nab-sirolimus dose to 56 mg/m2 during concomitant use of quinupristin. Coadministration may increase sirolimus concentrations and increase the risk for sirolimus-related adverse effects. Sirolimus is a CYP3A substrate and quinupristin is a weak CYP3A inhibitor.
Nicardipine: (Minor) Coadministration of dalfopristin; quinupristin and drugs metabolized primarily by CYP3A4 may result in increased plasma concentrations of these drugs that could increase or prolong their therapeutic effect and/or increase adverse reactions. Nicardipine is a substrate of CYP3A4 and other isoenzymes, and dalfopristin; quinupristin is a CYP3A4 inhibitor.
Nimodipine: (Moderate) Monitor blood pressure and watch for an increase in nimodipine-related adverse reactions if coadministration with dalfopristin; quinupristin is necessary; consider reducing the dose of nimodipine if needed. Nimodipine is a CYP3A4 substrate and dalfopristin; quinupristin is a weak CYP3A4 inhibitor; concomitant use may increase plasma concentrations of nimodipine.
Nisoldipine: (Major) Avoid coadministration of nisoldipine with dalfopristin; quinupristin due to increased plasma concentrations of nisoldipine. Nisoldipine is a CYP3A4 substrate and dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Norethindrone Acetate; Ethinyl Estradiol; Ferrous fumarate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Norethindrone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Norethindrone; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Norethindrone; Ethinyl Estradiol; Ferrous fumarate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Norgestimate; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Norgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Oral Contraceptives: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Oxycodone: (Moderate) Consider a reduced dose of oxycodone with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the oxycodone dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Oxycodone is a CYP3A4 substrate, and coadministration with a weak inhibitor like dalfopristin; quinupristin can increase oxycodone exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of oxycodone. If dalfopristin; quinupristin is discontinued, oxycodone plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to oxycodone.
Pimozide: (Major) Avoid concurrent use of pimozide and dalfopristin; quinupristin. Elevated pimozide concentrations occurring through inhibition of CYP3A4 can lead to QT prolongation, ventricular arrhythmias, and sudden death. Pimozide is metabolized primarily through CYP3A4, and dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Propafenone: (Moderate) Coadministration of propafenone with dalfopristin; quinupristin may result in elevated propafenone plasma concentrations. If these drugs are used together, closely monitor for signs of propafenone-related adverse events. Propafenone is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Quinidine: (Moderate) Coadministration of quinidine with dalfopristin; quinupristin may result in elevated quinidine plasma concentrations. If these drugs are used together, closely monitor for signs of quinidine-related adverse events. Quinidine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Relugolix; Estradiol; Norethindrone acetate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly.
Saxagliptin: (Major) The manufacturer recommends limiting the saxagliptin dose to 2.5 mg/day if used with strong CYP3A4/5 inhibitors such as dalfopristin; quinupristin. The metabolism of saxagliptin is primarily mediated by CYP3A4/5, and maximum serum concentrations and exposure of saxagliptin are increased when administered with strong inhibitors. Monitor patients for hypoglycemia if these drugs are used together.
Segesterone Acetate; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. Additionally, dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including ethinyl estradiol and norethindrone. In addition, drospirenone has antimineralocorticoid effects; the progestin may increase serum potassium. Consider monitoring serum potassium concentrations during the first month of dosing in high-risk patients who take strong CYP3A4 inhibitors long-term and concomitantly. (Minor) Coadministration of segesterone and strong CYP3A4 inhibitors such as streptogramins may increase the serum concentration of segesterone.
Sirolimus: (Moderate) Monitor sirolimus concentrations and adjust sirolimus dosage as appropriate during concomitant use of quinupristin. Coadministration may increase sirolimus concentrations and increase the risk for sirolimus-related adverse effects. Sirolimus is a CYP3A substrate and quinupristin is a weak CYP3A inhibitor.
Sodium picosulfate; Magnesium oxide; Anhydrous citric acid: (Major) Prior or concomitant use of antibiotics with sodium picosulfate; magnesium oxide; anhydrous citric acid may reduce efficacy of the bowel preparation as conversion of sodium picosulfate to its active metabolite bis-(p-hydroxy-phenyl)-pyridyl-2-methane (BHPM) is mediated by colonic bacteria. If possible, avoid coadministration. Certain antibiotics (i.e., tetracyclines and quinolones) may chelate with the magnesium in sodium picosulfate; magnesium oxide; anhydrous citric acid solution. Therefore, these antibiotics should be taken at least 2 hours before and not less than 6 hours after the administration of sodium picosulfate; magnesium oxide; anhydrous citric acid solution.
Sufentanil: (Moderate) Because the dose of the sufentanil sublingual tablets cannot be titrated, consider an alternate opiate if dalfopristin; quinupristin must be administered. Consider a reduced dose of sufentanil injection with frequent monitoring for respiratory depression and sedation if concurrent use of dalfopristin; quinupristin is necessary. If dalfopristin; quinupristin is discontinued, consider increasing the sufentanil injection dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Sufentanil is a CYP3A4 substrate, and coadministration with weak CYP3A4 inhibitors like dalfopristin; quinupristin can increase sufentanil exposure resulting in increased or prolonged opioid effects including fatal respiratory depression, particularly when an inhibitor is added to a stable dose of sufentanil. If the streptogramin is discontinued, sufentanil plasma concentrations will decrease resulting in reduced efficacy of the opioid and potential withdrawal syndrome in a patient who has developed physical dependence to sufentanil.
Tacrolimus: (Moderate) Monitor for increased tacrolimus adverse reactions if coadministered with dalfopristin; quinupristin. Taking these drugs together may increase tacrolimus plasma concentrations, potentially resulting in adverse events. Dalfopristin; quinupristin is a weak CYP3A4 inhibitor; tacrolimus is a substrate of CYP3A4 with a narrow therapeutic index.
Triazolam: (Moderate) Monitor for signs of triazolam toxicity during coadministration with quinupristin and consider appropriate dose reduction of triazolam if clinically indicated. Coadministration may increase triazolam exposure. Triazolam is a sensitive CYP3A substrate and quinupristin is a weak CYP3A inhibitor.
Ubrogepant: (Major) Limit the initial and second dose of ubrogepant to 50 mg if coadministered with quinupristin. Concurrent use may increase ubrogepant exposure and the risk of adverse effects. Ubrogepant is a CYP3A4 substrate; quinupristin is a weak CYP3A4 inhibitor.
Vinorelbine: (Moderate) Monitor for an earlier onset and/or increased severity of vinorelbine-related adverse reactions, including constipation and peripheral neuropathy, if coadministration with dalfopristin; quinupristin is necessary. Vinorelbine is a CYP3A4 substrate and dalfopristin; quinupristin is a weak CYP3A4 inhibitor.
Warfarin: (Moderate) Closely monitor the INR if coadministration of warfarin with streptogramins, like quinupristin, is necessary as concurrent use may increase the exposure of warfarin leading to increased bleeding risk. Streptogramins, like quinupristin, are weak CYP3A4 inhibitors and warfarin is a CYP3A4 substrate. Inhibition of vitamin K synthesis due to alterations in the intestinal flora may be a mechanism; however, concurrent infection is also a potential risk factor for elevated INR.

How Supplied

Synercid Intravenous Inj Pwd F/Sol: 150-350mg

Maximum Dosage
Adults

15 mg/kg/day IV is FDA-approved; however, doses up to 22.5 mg/kg/day IV have been used off-label.

Geriatric

15 mg/kg/day IV is FDA-approved; however, doses up to 22.5 mg/kg/day IV have been used off-label.

Adolescents

15 mg/kg/day IV is FDA-approved; however, doses up to 22.5 mg/kg/day IV have been used off-label.

Children

12 years: 15 mg/kg/day IV is FDA-approved; however, doses up to 22.5 mg/kg/day IV have been used off-label.
1 to 11 years: Safety and efficacy have not been established; however, doses up to 22.5 mg/kg/day IV have been used off-label.

Infants

Safety and efficacy have not been established; however, doses up to 22.5 mg/kg/day IV have been used off-label.

Neonates

Safety and efficacy have not been established.

Mechanism Of Action

Dalfopristin and quinupristin are two streptogramin antibiotics that act synergistically. Streptogramins inhibit bacterial protein synthesis by irreversibly blocking ribosome functioning. Dalfopristin binds to the 70S or 50S ribosomal particle and inhibits the early phase of protein synthesis; quinupristin binds to the 50S subunit of the 70S bacterial ribosome and inhibits the late phase of protein synthesis. The binding of both agents to the ribosome constricts the exit channel on the ribosome through which nascent polypeptides are extruded; proper functioning of the ribosome is blocked and transfer RNA (tRNA) synthetase activity is inhibited leading to a decrease in free tRNA within the cell. Without these tRNAs, the bacterial cell cannot properly incorporate amino acids into peptide chains and this leads to bacterial cell death. The activity of dalfopristin; quinupristin is bactericidal against staphylococci and streptococci, but may be bacteriostatic for enterococci.

Pharmacokinetics

Dalfopristin; quinupristin (Synercid) is administered by intravenous infusion. In humans, dalfopristin and quinupristin are the main active components circulating in plasma. Protein binding of Synercid is moderate. Penetration of unchanged dalfopristin and quinupristin in noninflammatory blister fluid correlates to about 11% and 19% of that estimated in plasma, respectively. The penetration into blister fluid of dalfopristin and quinupristin in combination with their major metabolites was in total about 40% compared to that in plasma.
 
Dalfopristin and quinupristin are converted to several active major metabolites; one non-conjugated metabolite for dalfopristin (formed by hydrolysis) and two conjugated metabolites for quinupristin (one with glutathione and one with cysteine). In vitro, the transformation of the parent drugs into their major active metabolites occurs by non-enzymatic reactions and is not dependent on cytochrome P450 or glutathione-transferase enzyme activities. However, Synercid has been shown to be a major inhibitor of the activity of cytochrome P450 3A4 isoenzyme.
 
The main route of elimination for both dalfopristin and quinupristin and their metabolites (75—77% of an administered dose) is fecal excretion. Urinary excretion accounts for approximately 19% of the dalfopristin and 15% of the quinupristin dose. Preclinical animal data have shown that approximately 80% of an administered dose is excreted in the bile and suggest that in man, biliary excretion is probably the principal route for fecal elimination. The elimination half-lives of dalfopristin and quinupristin are approximately 0.70 and 0.85 hours, respectively. 

Intravenous Route

The Cmax for dalfopristin and quinupristin following q8h dosing is about 8 mcg/mL and 3 mcg/mL, respectively.

Pregnancy And Lactation
Pregnancy

There are no adequate and well controlled studies of dalfopristin; quinupristin use during human pregnancy. Animal data have revealed no evidence that dalfopristin; quinupristin impairs fertility or harms the fetus. Because animal reproduction studies are not always predictive of the human response, use dalfopristin; quinupristin during pregnancy only if clearly needed.

Use dalfopristin; quinupristin with caution in breast-feeding women. It is not known whether dalfopristin; quinupristin is excreted in human breast milk. Due to its large molecular weight and the fact that dalfopristin; quinupristin is weakly acidic, excretion into breast milk may be limited. Vancomycin, daptomycin, clindamycin, and sulfamethoxazole; trimethoprim may be potential alternatives to consider during breast-feeding. Site of infection, patient factors, local susceptibility patterns, and specific microbial susceptibility should be assessed before choosing an alternative agent. Vancomycin is excreted in breast milk; however, absorption from the GI tract of any ingested vancomycin would be minimal. Daptomycin has a high molecular weight; therefore, excretion into breast milk may be limited. In 1 patient with daptomycin breast milk concentration measured on day 27 of therapy (dose of 6.7 mg/kg IV), a peak concentration of 44.7 mcg/L was obtained 8 hours after the dose with an estimated milk:plasma ratio of 0.0012. Alternative antimicrobials that previous American Academy of Pediatrics recommendations considered as usually compatible with breast-feeding include clindamycin and sulfamethoxazole; trimethoprim.