Imatinib and Ketoconazole Topical: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Imatinib
Ketoconazole Topical
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 imatinib exposure and an increased ketoconazole exposure
Interaction Deep Dive
A significant increase in peak plasma concentrations and area under the concentration-time curve (AUC) of imatinib was observed when the drug was coadministered with a single dose of ketoconazole. However, single dose interaction pharmacokinetics may not accurately reflect toxicity potential for higher therapeutic doses of imatinib given concurrently with a multiple dose regimen of ketoconazole3. Caution is advised when using imatinib, a strong CYP3A4 inhibitor and substrate, with a strong CYP3A4 inhibitor and substrate such as ketoconazole as coadministration may result in elevated exposure of either agent 12. If concomitant use is required, monitor patient for signs and symptoms of increased or prolonged pharmacologic effects of ketoconazole/imatinib and reduce imatinib/ketoconazole dosage as deemed necessary 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of imatinib; inhibition of CYP3A4-mediated metabolism of ketoconazole
Literature reports
1 report — tap to read
a) Coadministration of imatinib with ketoconazole significantly increased imatinib exposure. In an open-label, randomized, crossover study, healthy subjects (n=14) received a single oral dose of imatinib 200 milligrams (mg) with or without a single oral dose of ketoconazole 400 mg. Each subject crossed over to the opposite treatment arm following a 7-day washout period. Serial blood analysis was performed over 96 hours after dosing in each treatment phase. The presence of ketoconazole elicited significant elevations in imatinib mean maximum serum concentration and area under the concentration-time curve (AUC 0-24 hours) (by 26% and 40%, respectively; p less than 0.005, both parameters). Imatinib mean clearance was significantly reduced after concomitant administration with ketoconazole (by 28.6%; p less than 0.005). The study authors observe that the single-dose interaction pharmacokinetics of the study may not accurately reflect the potential for imatinib toxicity when higher doses of imatinib (800 mg daily or higher) are given in the presence of a ketoconazole multiple dose regimen 3.
Common questions
Can I take Imatinib and Ketoconazole Topical together?
Increased imatinib exposure and an increased ketoconazole exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Imatinib 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 "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
Questions for your pharmacist
- Does my dose of Imatinib 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 (3)
- Product Information: Ketoconazole oral tablet, ketoconazole oral tablet. Taro Pharmaceuticals U.S.A. Inc. (per DailyMed), Hawthorne, NY, 2024. DailyMed
- Product Information: GLEEVEC(R) oral tablets, imatinib mesylate oral tablets. Novartis Pharmaceuticals Corporation (per FDA), East Hanover, NJ, 2022. DailyMed
- Dutreix C, Peng B, Mehring G, et al: Pharmacokinetic interaction between ketoconazole and imatinib mesylate (Glivec) in healthy subjects. Cancer Chemother Pharmacol 2004; 54:290-294. DOI
Keep reading about Imatinib
Keep reading about Ketoconazole Topical
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