Itraconazole and Avanafil: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Itraconazole
Avanafil
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased avanafil exposure and an increased risk of avanafil-related adverse effects
Interaction Deep Dive
Coadministration of avanafil and itraconazole is contraindicated during and for 2 weeks after itraconazole therapy23 as this may result in increased avanafil exposure and toxicity. Compared with the pharmacokinetics of avanafil alone, the administration of a single dose of avanafil 50 mg with ketoconazole 400 mg/day (also a strong CYP3A4 inhibitor) resulted in a 13-fold increase in AUC, 3.1-fold increase in Cmax, and a prolonged half-life of 9 hours for avanafil. Although not specifically studied with itraconazole, other strong CYP3A4 inhibitors would be expected to have similar effects. Itraconazole and avanafil should not be used concomitantly 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of avanafil by itraconazole; reduced avanafil clearance
Literature reports
1 report — tap to read
a) Compared with the pharmacokinetics of avanafil alone, the administration of a single dose of avanafil 50 mg with ketoconazole 400 mg/day (also a strong CYP3A4 inhibitor) resulted in a 13-fold increase in AUC, 3.1-fold increase in Cmax, and a prolonged half-life of 9 hours for avanafil. Although not specifically studied with itraconazole, other strong CYP3A4 inhibitors would be expected to have similar effects 1.
Common questions
Can I take Itraconazole and Avanafil together?
Increased avanafil exposure and an increased risk of avanafil-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Itraconazole and Avanafil interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Itraconazole or Avanafil need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (3)
- Product Information: STENDRA(R) oral tablets, avanafil oral tablets. Metuchen Pharmaceuticals LLC (per FDA), Freehold, NJ, 2022. DailyMed
- Product Information: SPORANOX(R) oral solution, itraconazole oral solution. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
- Product Information: SPORANOX(R) oral capsules, itraconazole oral capsules. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
Keep reading about Itraconazole
Keep reading about Avanafil
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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