Ketoconazole Topical and Copanlisib: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ketoconazole Topical
Copanlisib
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 copanlisib plasma levels and risk of toxicity
Interaction Deep Dive
Concomitant use of copanlisib and a strong CYP3A inhibitor increases the exposure of copanlisib and the risk of toxicity. Copanlisib is more than 90% metabolized by CYP3A and coadministration with itraconazole (a strong CYP3A inhibitor) resulted in a 53% increase in copanlisib exposure. Concomitant use should be avoided. If coadministration is required, reduce the copanlisib dose to 45 mg1.
Why it happens (mechanism)
Inhibition of CYP3A-mediated copanlisib metabolism
Literature reports
1 report — tap to read
a) Coadministration of a single infusion of copanlisib 60 mg IV in cancer patients receiving itraconazole (a strong CYP3A inhibitor) 200 mg once daily for 10 days increased the mean AUC of copanlisib by 53% with no significant effect on Cmax 1.
Common questions
Can I take Ketoconazole Topical and Copanlisib together?
Increased copanlisib plasma levels and risk of toxicity Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ketoconazole Topical and Copanlisib interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
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 "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Ketoconazole Topical or Copanlisib 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 (1)
- Product Information: ALIQOPA(TM) intravenous injection, copanlisib intravenous injection. Bayer HealthCare Pharmaceuticals Inc (per FDA), Whippany, NJ, 2017.
Keep reading about Ketoconazole Topical
Keep reading about Copanlisib
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