Alprazolam and Ketoconazole interaction
Alprazolam 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 Alprazolam (Alprazolam XR) label · effective 2025-02-11
• taking strong cytochrome P450 3A (CYP3A) inhibitors (e.g., ketoconazole, itraconazole), except ritonavir [see Dosage and Administration (2.5) , Warnings and Precautions (5.5) , Drug Interactions (7.1) ] .
• Concomitant use with strong cytochrome P450 3A (CYP3A) inhibitors, except ritonavir.
Strong CYP3A Inhibitors Alprazolam XR is contraindicated in patients receiving strong inhibitors of CYP3A such as azole antifungal agents [see Contraindications (4) ] .
Prevention or management Concomitant use of alprazolam XR with a strong CYP3A4 inhibitor (except ritonavir) is contraindicated [see Contraindications (4) , Warnings and Precautions (5.5) ] .
Prevention or management Avoid use and consider appropriate dose reduction when alprazolam XR is coadministered with a moderate or weak CYP3A inhibitor [see Warnings and Precautions (5.5) ] .
From the Ketoconazole label · effective 2026-07-07
…contraindicated with ketoconazole tablets: methadone, disopyramide, dronedarone, ergot alkaloids such as dihydroergotamine, ergometrine, ergotamine, methylergometrine, irinotecan, lurasidone, oral midazolam, alprazolam, triazolam, felodipine, nisoldipine, ranolazine, tolvaptan, eplerenone, lovastatin, simvastatin and colchicine (see PRECAUTIONS: Drug Interactions ).
Enhanced Sedation Coadministration of ketoconazole tablets with oral midazolam, oral triazolam or alprazolam has resulted in elevated plasma concentrations of these drugs.
Concomitant administration of ketoconazole tablets with oral triazolam, oral midazolam or alprazolam is contraindicated (see PRECAUTIONS: Drug Interactions ).
This may potentiate and prolong hypnotic and sedative effects, especially with repeated dosing or chronic administration of these agents.
…methadone when coadministered with ketoconazole tablets may increase the risk of serious cardiovascular events including QT prolongation and torsade de pointes, or respiratory or CNS depression [See CONTRAINDICATIONS .] Fentanyl: The potential increase in plasma concentrations of fentanyl when coadministered with ketoconazole tablets may increase the risk of…
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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.