Etravirine and Posaconazole interaction
Etravirine and Posaconazole: 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 Posaconazole (NOXAFIL) label · effective 2026-02-13
Anti-HIV Drugs that are CYP3A4 Substrates Mechanism and Clinical Effect(s) Ritonavir and atazanavir are CYP3A4 substrates and posaconazole increased plasma concentrations of these drugs [see Clinical Pharmacology (12.3) ].
From the Etravirine label · effective 2025-04-02
Dose adjustments for itraconazole, ketoconazole or posaconazole may be necessary depending on the other co-administered drugs.
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 : fluconazole ↑ etravirine ↔ fluconazole Co-administration of etravirine and fluconazole significantly increased etravirine exposures.
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) ].
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.