Itraconazole and Avanafil
Desk tier: Avoid together
Mechanism: strong CYP3A4 inhibition of clearance (↑ exposure)
“Coadministration of a number of CYP3A4 substrates are contraindicated with SPORANOX®.”
Why this grade
Sporanox (itraconazole) label, Contraindications
The Sporanox (itraconazole) label lists this combination under Contraindications. CONTRAINDICATIONS: "Coadministration of a number of CYP3A4 substrates are contraindicated with SPORANOX®." Named in the label: "avanafil" Retrieved from DailyMed 2026-10-02.
Open sourceFDA interaction table
FDA's example-interaction table lists Itraconazole as a strong CYP3A inhibitor, and Avanafil as a sensitive CYP3A substrate. FDA grades the roles; the severity tier on this row is the desk's rule. Table content current as of 2026-05-29.
Open sourceItraconazole label, Contraindications
The Itraconazole label calls this combination contraindicated: "Coadministration of a number of CYP3A4 substrates are contraindicated with itraconazole. Some examples of drugs for which plasma concentrations increase are: methadone, disopyramide, dofetilide, dronedarone, quinidine, isavuconazole, ergot alkaloids (such as dihydroergotamine, ergometrine (ergonovine), ergotamine, methylergometrine (methylergonovine)), irinotecan, lurasidone, oral midazolam, pimozide, triazolam, felodipine, nisoldipine, ivabradine, ranolazine, eplerenone, cisapride, naloxegol, lomitapide, lovastatin, simvastatin, avanafil, ticagrelor, finerenone, voclosporin." Retrieved from DailyMed 2026-10-02.
Open sourcePMID 9591931
1998 Eur J Clin Pharmacol. Backman. Switch from inhibition to induction is a 400-fold swing. Four days after rifampin, AUC is still only 13% of baseline — the stop clock.
Open sourceAll pairs for Itraconazole · Avanafil
Enzyme behind this pair: CYP3A4
Educational reference only. Not FDA-cleared. The Prescribing Information governs.
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