Darunavir and cobicistat and Dexamethasone interaction
Darunavir and cobicistat and Dexamethasone: 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
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.
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.
Co-administration of PREZCOBIX or PREZCOBIX PED and drugs that induce CYP3A activity are expected to increase the clearance of darunavir and cobicistat, resulting in lowered plasma concentrations of darunavir and cobicistat which may lead to loss of therapeutic effect and development of resistance.
Corticosteroids: dexamethasone (systemic) Corticosteroids primarily metabolized by CYP3A: e.g. betamethasone budesonide ciclesonide fluticasone methylprednisolone mometasone triamcinolone ↓ darunavir ↓ cobicistat ↑ corticosteroids Co-administration with systemic dexamethasone or other systemic corticosteroids that induce CYP3A may result in loss of therapeutic…
From the Dexamethasone (Hemady) label · effective 2026-01-09
• Avoid concomitant use of strong CYP3A4 inhibitors or inducers.
Avoid coadministration of strong CYP3A4 inhibitors or consider alternative medication that are not strong CYP3A4 inhibitors.
If concomitant use of strong CYP3A4 inhibitors cannot be avoided, closely monitor for adverse drug reactions.
( 7.2 ) 7.1 Effect of Other Drugs on HEMADY Strong CYP3A4 inhibitors Coadministration of strong and moderate CYP3A4 inhibitors increased dexamethasone exposure [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of adverse reactions [see Warnings and Precautions ( 5 ) and Adverse Reactions ( 6 )] .
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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.