Ketoconazole and Lopinavir and ritonavir interaction
Ketoconazole and Lopinavir and ritonavir: 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
Therefore, administration of potent enzyme inducers of CYP3A4 with ketoconazole tablets is not recommended.
Drugs that may increase ketoconazole plasma concentrations Potent inhibitors of CYP3A4 (e.g., antivirals such as ritonavir, ritonavir-boosted darunavir and ritonavir-boosted fosamprenavir) may increase the bioavailability of ketoconazole.
Coadministration of ketoconazole tablets with potent enzyme inducers of CYP3A4 may decrease the bioavailability of ketoconazole to such an extent that efficacy may be reduced.
From the Lopinavir and ritonavir (Kaletra) label · effective 2026-07-23
Antifungals: ketoconazole*, itraconazole, voriconazole isavuconazonium sulfate* ↑ ketoconazole ↑ itraconazole ↓ voriconazole ↑ isavuconazonium High doses of ketoconazole (>200 mg/day) or itraconazole (> 200 mg/day) are not recommended.
Avoid use in patients with congenital long QT syndrome, those with hypokalemia, and with other drugs that prolong the QT interval.
Potential for KALETRA to Affect Other Drugs Lopinavir/ritonavir is an inhibitor of CYP3A and may increase plasma concentrations of agents that are primarily metabolized by CYP3A.
Although not observed in the KALETRA/ketoconazole drug interaction study, co-administration of KALETRA and other drugs that inhibit CYP3A may increase lopinavir plasma concentrations.
Alternative antifungal therapies should be considered in these patients.
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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.