Drug Interaction Report

Irinotecan Injection and Itraconazole: Interaction Details

A pharmacist-reviewed analysis of the Irinotecan Injection and Itraconazole interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Itraconazole

Sporanox Tolsura
+

Irinotecan Injection

Camptosar Camptosar® Onivyde
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Contraindicated
These should generally not be used together.
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.

Of 96 documented Irinotecan Injection interactions, 14 are rated contraindicated — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
theoretical
Severity
Contraindicated

What happens

Increased irinotecan exposure

Interaction Deep Dive

Concomitant use of irinotecan (a CYP3A4 substrate) and itraconazole (a strong CYP3A4 inhibitor) is contraindicated as well as up to 2 weeks after discontinuation of itraconazole treatment, as this may increase the exposure of irinotecan and increase the risk of fatal adverse effects12.

Why it happens (mechanism)

Inhibition of CYP3A4-mediated irinotecan metabolism by itraconazole

Common questions

Can I take Irinotecan Injection and Itraconazole together?

Increased irinotecan exposure Always confirm with your pharmacist or prescriber before making any change.

How serious is the Irinotecan Injection and Itraconazole 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 Irinotecan Injection or Itraconazole 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 (2)

  1. Product Information: SPORANOX(R) oral capsules, itraconazole oral capsules. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
  2. Product Information: SPORANOX(R) oral solution, itraconazole oral solution. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
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Itraconazole

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All Itraconazole interactions (206)
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Irinotecan Injection

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All Irinotecan Injection interactions (96) Irinotecan Injection drug information
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Beyond drug–drug

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:

Itraconazole + Activated Charcoal Beer Grapefruit Siberian Cocklebur St. John's Wort Wine Acacia Rigidula Adrafinil + 174 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.