Ketoconazole and Posaconazole interaction
Ketoconazole and Posaconazole: 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 Posaconazole (NOXAFIL) label · effective 2026-02-13
Known hypersensitivity to posaconazole or other azole antifungal agents.
Hypersensitivity Noxafil is contraindicated in persons with known hypersensitivity to posaconazole or other azole antifungal agents.
Effects of Noxafil and Noxafil PowderMix on Other Drugs Posaconazole is a strong CYP3A4 inhibitor.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.