FTC (emtricitabine, Emtriva) is excreted via the kidneys. With the exception of famciclovir (Famvir) and tenofovir (Viread), interactions between FTC and other drugs that are excreted by the kidneys or that affect kidney function have not been assessed. There is no significant interaction between FTC and famciclovir or tenofovir.

FTC has a low potential for interaction with other drugs, and does not inhibit metabolism by the cytochrome P450 system. To date, clinical studies have found no significant interactions between FTC and indinavir (Crixivan), AZT (zidovudine, Retrovir) or d4T (stavudine, Zerit).

There have been no studies analysing the interaction between FTC and other nucleoside reverse transcriptase inhibitors (NRTIs) in the cytosine analogue group, i.e. 3TC (lamivudine, Epivir) and ddC (zalcitabine, Hivid). As they have very similar modes of action, the co-administration of FTC with either of these drugs is not recommended.