Buspirone and Ketoconazole interaction
Buspirone and Ketoconazole: 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
If a patient has been titrated to a stable dosage on buspirone, a dose reduction of buspirone may be necessary to avoid adverse events attributable to buspirone or diminished anxiolytic activity.
Antipsychotics, Anxiolytics and Hypnotics Lurasidone, alprazolam, oral midazolam, pimozide, triazolam aripiprazole, buspirone, haloperidol, midazolam IV, quetiapine, ramelteon, risperidone The increase in plasma concentrations of lurasidone when coadministered with ketoconazole tablets may increase the risk of serious side effects (See CONTRAINDICATIONS ).
Buspirone: Ketoconazole is expected to inhibit buspirone metabolism and increase plasma concentrations of buspirone.
From the Buspirone (Buspirone Hydrochloride) label · effective 2026-03-18
Other inhibitors and inducers of CYP3A4: Substances that inhibit CYP3A4, such as ketoconazole or ritonavir, may inhibit buspirone metabolism and increase plasma concentrations of buspirone while substances that induce CYP3A4, such as dexamethasone or certain anticonvulsants (phenytoin, phenobarbital, carbamazepine), may increase the rate of buspirone metabolism.
Consequently, when administered with a potent inhibitor of CYP3A4, a low dose of buspirone used cautiously is recommended.
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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.