Darunavir and cobicistat and Efavirenz interaction
Darunavir and cobicistat and Efavirenz: 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 Efavirenz label · effective 2024-03-31
Protease inhibitor: Lopinavir/ritonavir ↓ lopinavir * Lopinavir/ritonavir once daily dosing is not recommended when coadministered with efavirenz.
…Alteration in Dose or Regimen May Be Recommended Based on Drug Interaction Studies or Predicted Interaction Concomitant Drug Class: Drug Name Effect Clinical Comment HIV antiviral agents Protease inhibitor: Fosamprenavir Calcium ↓ amprenavir Fosamprenavir (unboosted): Appropriate doses of the combinations with respect to safety and efficacy have not been established.
Protease inhibitor: Atazanavir ↓ atazanavir * Treatment-naive patients: When coadministered with efavirenz, the recommended dose of atazanavir is 400 mg with ritonavir 100 mg (together once daily with food) and efavirenz 600 mg (once daily on an empty stomach, preferably at bedtime).
Protease inhibitor: Indinavir ↓ indinavir * The optimal dose of indinavir, when given in combination with efavirenz, is not known.
Protease inhibitor: Ritonavir ↑ ritonavir * ↑ efavirenz * Monitor for elevation of liver enzymes and for adverse clinical experiences (e.g., dizziness, nausea, paresthesia) when efavirenz is coadministered with ritonavir.
From the Darunavir and cobicistat (PREZCOBIX) label · effective 2026-02-01
HIV-1 antiviral agents: Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) efavirenz ↓ cobicistat ↓ darunavir Co-administration with efavirenz is not recommended because it may result in loss of therapeutic effect and development of resistance to darunavir. etravirine ↓ cobicistat darunavir: effect unknown Co-administration with etravirine is not recommended…
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.
Anticonvulsants with CYP3A induction effects that are NOT contraindicated: e.g. eslicarbazepine, oxcarbazepine ↓ cobicistat darunavir: effect unknown Consider alternative anticonvulsant or antiretroviral therapy to avoid potential changes in exposures.
Initiation of medications that inhibit or induce CYP3A may respectively increase or decrease concentrations of PREZCOBIX or PREZCOBIX PED.
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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.