Ketoconazole Topical and Fingolimod: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ketoconazole Topical
Fingolimod
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 fingolimod exposure and an increased risk of QT interval prolongation
Interaction Deep Dive
Concomitant use of fingolimod and ketoconazole, a potent CYP3A4 and CYP4F inhibitor may increase risk of QT interval prolongation12 and is not recommended as this may increase fingolimod exposure and a greater risk of adverse effects due to inhibition of CYP3A4- and CYP4F-mediated fingolimod metabolism. A 70% increase in the AUC of fingolimod and fingolimod-phosphate was reported when patients were given a single 5-mg dose of fingolimod after being on ketoconazole 200 mg twice daily at steady-state. Additionally, concomitant use may result in additive QT interval prolongation effect. If concomitant use cannot be avoided, patients should be closely monitored when fingolimod and systemic ketoconazole are coadministered as there is a greater risk of adverse reactions 2.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of fingolimod; inhibition of CYP4F-mediated metabolism of fingolimod; additive QT interval prolongation
Literature reports
1 report — tap to read
a) A 70% increase in the AUC of fingolimod and fingolimod-phosphate was reported when patients were given a single 5-mg dose of fingolimod after being on ketoconazole 200 mg twice daily at steady-stat 2.
Common questions
Can I take Ketoconazole Topical and Fingolimod together?
Increased fingolimod exposure and an increased risk of QT interval prolongation Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ketoconazole Topical and Fingolimod 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 Ketoconazole Topical or Fingolimod 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: Ketoconazole oral tablet, ketoconazole oral tablet. Taro Pharmaceuticals U.S.A. Inc. (per DailyMed), Hawthorne, NY, 2024. DailyMed
- Product Information: GILENYA(TM) oral capsules, fingolimod oral capsules. Novartis Pharmaceuticals Corporation (per FDA), East Hanover, NJ, 2012. DailyMed
Keep reading about Ketoconazole Topical
Keep reading about Fingolimod
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