Sonidegib and Ketoconazole Topical: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ketoconazole Topical
Sonidegib
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 sonidegib exposure
Interaction Deep Dive
The concomitant use of sonidegib, a CYP3A substrate, with a strong CYP3A inhibitor may result in increased sonidegib exposure and increase the risk of adverse effects1. When sonidegib was coadministered with the strong CYP3A inhibitor, ketoconazole, the AUC increased 2.25 fold and Cmax increased 1.49 fold compared with sonidegib alone 2. Therefore, it is recommended that coadministration of sonidegib with a strong CYP3A inhibitor be avoided 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of sonidegib
Literature reports
1 report — tap to read
a) In a pharmacokinetic study of 31 healthy volunteers, the mean AUC(0 to 10 days) increased 2.25-fold and the Cmax increased 1.49-fold when sonidegib 800 mg single-dose was administered 5 days after initiating oral ketoconazole 200 mg twice daily, compared with sonidegib single-dose alone. Simulated clinical pharmacokinetic parameters in cancer patients suggest that a dose modification to sonidegib 200 mg every other day compared with daily dosing in the presence of ketoconazole (a strong CYP3A inhibitor) would result in a less than 2-fold increase in AUC(0 to 24) at steady state 2.
Common questions
Can I take Sonidegib and Ketoconazole Topical together?
Increased sonidegib exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Sonidegib and Ketoconazole Topical 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Sonidegib or Ketoconazole Topical 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)
- Product Information: ODOMZO(R) oral capsules, sonidegib oral capsules. Novartis Pharmaceuticals (per FDA), East Hanover, NJ, 2015. DailyMed
- Einolf HJ, Zhou J, Won C, et al: A physiologically-based pharmacokinetic modeling approach to predict drug-drug interactions of sonidegib (LDE225) with perpetrators of CYP3A in cancer patients. Drug Metab Dispos 2017; 45(4):361-374. PubMed
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