Darunavir and cobicistat and Fosamprenavir interaction
Darunavir and cobicistat and Fosamprenavir: 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
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…
Co-administration of PREZCOBIX or PREZCOBIX PED and other drugs that inhibit CYP3A may result in increased plasma concentrations of darunavir and cobicistat (see Table 2 ).
For additional recommendations on use of PREZCOBIX or PREZCOBIX PED with other antiretroviral agents, [see Drug Interactions (7) ] .
From the Fosamprenavir (Fosamprenavir Calcium) label · effective 2026-06-30
Because ritonavir is a CYP2D6 inhibitor, clinically significant interactions with drugs metabolized by CYP2D6 are possible when coadministered with fosamprenavir calcium plus ritonavir.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.