Bexarotene 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
Bexarotene
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 bexarotene exposure
Interaction Deep Dive
Bexarotene oxidative metabolites are formed by cytochrome P450 3A4 (CYP3A4) enzymes. Although no specific studies have been conducted to evaluate drug interactions with bexarotene, it is expected that inhibitors of CYP3A4, such as ketoconazole, would increase plasma bexarotene concentrations1.
Why it happens (mechanism)
Inhibition of cytochrome P450-3A4 mediated bexarotene metabolism
Common questions
Can I take Bexarotene and Ketoconazole Topical together?
Increased bexarotene exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Bexarotene and Ketoconazole Topical interaction?
It is rated moderate. Can be significant — usually manageable with 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 Bexarotene 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 anything you'd monitor while I'm on both?
References (1)
- Product Information: Targretin(R), bexarotene. Ligand Pharmaceuticals Incorporated, San Diego, CA, 2003. DailyMed
Keep reading about Ketoconazole Topical
Keep reading about Bexarotene
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:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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