Ketoconazole and Voriconazole interaction
Ketoconazole and Voriconazole: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Ketoconazole label · effective 2026-07-07
Ketoconazole tablets should be used only when other effective antifungal therapy is not available or tolerated and the potential benefits are considered to outweigh the potential risks.
This effect is not shared with other azoles.
From the Voriconazole label · effective 2026-06-02
There is no information regarding cross-sensitivity between voriconazole and other azole antifungal agents.
Refer to the prescribing information for other azole antifungal agents.
Other HIV Protease Inhibitors (CYP3A4 Inhibition) In Vivo Studies Showed No Significant Effects of Indinavir on Voriconazole Exposure In Vitro Studies Demonstrated Potential for Inhibition of Voriconazole Metabolism (Increased Plasma Exposure) No dosage adjustment in the voriconazole dosage needed for concomitant administration with indinavir.
Prednisolone and other corticosteroids (CYP3A4 Inhibition) In Vivo Studies Showed No Significant Effects of voriconazole on Prednisolone Exposure Not Studied In Vitro or In Vivo for Other Corticosteroids, but Drug Exposure Likely to be Increased No dosage adjustment for prednisolone when concomitantly administered with voriconazole [see Clinical Pharmacology…
Other HIV Protease Inhibitors (CYP3A4 Inhibition) In Vivo Studies Showed No Significant Effects on Indinavir Exposure No dosage adjustment for indinavir when concomitantly administered with voriconazole.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.