Darunavir and cobicistat and Lopinavir and ritonavir interaction
Darunavir and cobicistat 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 Darunavir and cobicistat (PREZCOBIX) label · effective 2026-02-01
Post-marketing cases of liver injury, including some fatalities, have also been reported with darunavir co-administered with ritonavir.
PREZCOBIX or PREZCOBIX PED is not recommended in combination with products containing the individual components of PREZCOBIX or PREZCOBIX PED (darunavir and cobicistat) or with ritonavir.
Co-administration of PREZCOBIX or PREZCOBIX PED with CYP3A inducers may lead to lower exposures of darunavir and cobicistat and potential loss of efficacy of darunavir and possible resistance.
PREZCOBIX or PREZCOBIX PED is not recommended in combination with other antiretroviral drugs that require pharmacokinetic boosting.
Antiretrovirals Not Recommended PREZCOBIX or PREZCOBIX PED is not recommended in combination with other antiretroviral drugs that require pharmacokinetic boosting (i.e., another protease inhibitor or elvitegravir) because dosing recommendations for such combinations have not been established and co-administration may result in decreased plasma concentrations…
From the Lopinavir and ritonavir (Kaletra) label · effective 2026-07-23
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.
Patients who exhibit these signs or symptoms should be evaluated and KALETRA and/or other antiretroviral therapy should be suspended as clinically appropriate.
Elevated transaminases with or without elevated bilirubin levels have been reported in HIV-1 mono-infected and uninfected patients as early as 7 days after the initiation of KALETRA in conjunction with other antiretroviral agents.
Antimycobacterial: rifampin ↓ lopinavir Contraindicated due to potential loss of virologic response and possible resistance to KALETRA or to the class of protease inhibitors or other co-administered antiretroviral agents [see Contraindications ( 4 )] .
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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.