Etravirine and Ivacaftor interaction
Etravirine and Ivacaftor: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Ivacaftor (Kalydeco) label · effective 2026-03-23
Concomitant Use with CYP3A Inducers Use of KALYDECO with strong CYP3A inducers, such as rifampin, substantially decreases the exposure of ivacaftor, which may reduce the therapeutic effectiveness of KALYDECO.
Inducers of CYP3A Co-administration with rifampin, a strong CYP3A inducer, significantly decreased ivacaftor exposure (AUC) by approximately 9-fold.
Use with CYP3A inducers: Concomitant use with strong CYP3A inducers (e.g., rifampin, St.
Therefore, co-administration of KALYDECO with strong CYP3A inducers (e.g., rifampin, St.
Therefore, co-administration with strong CYP3A inducers, such as rifampin, rifabutin, phenobarbital, carbamazepine, phenytoin, and St.
From the Etravirine label · effective 2025-04-02
CCR5 antagonists maraviroc ↔ etravirine ↓ maraviroc When Etravirine is co-administered with maraviroc in the absence of a potent CYP3A inhibitor (e.g., ritonavir boosted protease inhibitor), the recommended dose of maraviroc is 600 mg twice daily.
Antifungals : itraconazole ketoconazole posaconazole ↑ etravirine ↓ itraconazole ↓ ketoconazole ↔ posaconazole Posaconazole, a potent inhibitor of CYP3A4, may increase plasma concentrations of etravirine.
Therefore, co-administration of Etravirine with drugs that induce or inhibit CYP3A, CYP2C9, and CYP2C19 may alter the therapeutic effect or adverse reaction profile of Etravirine (see Table 4 ) [see Clinical Pharmacology (12.3) ].
…maraviroc/darunavir/ ritonavir The reference for etravirine exposure is the pharmacokinetic parameters of etravirine in the presence of darunavir/ritonavir. ↔ etravirine ↑ maraviroc When Etravirine is co-administered with maraviroc in the presence of a potent CYP3A inhibitor (e.g., ritonavir boosted protease inhibitor), the recommended dose of maraviroc is 150 mg twice daily.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.