Rifampicin bioavailability is increased by indinavir, but
amprenavir has no effect.
Rifampicin markedly reduces the bioavailability of
amprenavir,
atazanavir, indinavir, lopinavir, nelfinavir and saquinavir.
The use of many of the
protease inhibitors with
rifampicin is contraindicated. The treatment of
tuberculosis in patients taking antiretrovirals is complex and up-to- date guidelines should be consulted.