Irinotecan and Ketoconazole: Drug Interaction Guide

Quick answer: This is a major interaction — avoid combining Irinotecan and Ketoconazole unless specifically directed by your doctor.

Interaction severity: Major — avoid combination

How Irinotecan interacts with Ketoconazole

Ketoconazole inhibits CYP3A4 and UGT1A1, increasing exposure to irinotecan's active metabolite SN-38 with severe neutropenia and diarrhea.

What you should do

Avoid azole antifungals during irinotecan therapy; use micafungin or amphotericin B if antifungal coverage is needed.

Key facts

Severity

Major — avoid combination

Mechanism

Ketoconazole inhibits CYP3A4 and UGT1A1, increasing exposure to irinotecan's active metabolite SN-38 with severe neutrop...

Action

Avoid azole antifungals during irinotecan therapy; use micafungin or amphotericin B if antifungal coverage is needed.

Important medical disclaimer: This page provides educational information about drug interactions for general reference. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your specific medications with a qualified healthcare provider before starting, stopping, or changing any treatment. About our editorial team.

Frequently asked questions

Can I take Irinotecan and Ketoconazole together?

No — this combination should generally be avoided. Avoid azole antifungals during irinotecan therapy; use micafungin or amphotericin B if antifungal coverage is needed.

What is the severity of this interaction?

The interaction between Irinotecan and Ketoconazole is classified as Major — avoid combination. Ketoconazole inhibits CYP3A4 and UGT1A1, increasing exposure to irinotecan's active metabolite SN-38 with severe neutropenia and diarrhea.

What should I do if I'm prescribed both?

Avoid azole antifungals during irinotecan therapy; use micafungin or amphotericin B if antifungal coverage is needed. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

Last reviewed: by iMedic Medical Editorial Team. Our editorial process.