Rifampicin atazanavir + ritonavir

Clinically important, potentially hazardous interactions with atazanavir, carbamazepine, clarithromycin, dexamethasone, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, phenobarbital, phenytoin, rifabutin, rifampicin, rifampin, ritonavir, saquinavir, St John s wort, telithromycin, voriconazole... 

Rifampicin (rifampin) bioavaiiabiiity is increased by indinavir, but amprenavir has no effect. Rifampicin markedly reduces the bioavailability of amprenavir, atazanavir/ritonavir, indinavir, indinavir with ritonavir, iopinavir/ritonavir, nelfinavir and saquinavir, but oniy modestiy reduces that of ritonavir. The effects of rifampicin on iopinavir/ritonavir and saquinavir/ritona-vir can be overcome by increasing the protease inhibitor dose, but this appears to increase adverse effects (hepatotoxicity). 

Rifampicin (Rifampin). When rifampicin 600 mg daily was given with atazanavir/ritonavir 300/100 mg once daily, the AUC and minimum levels of atazanavir were markedly reduced, by 72% and 98%, respectively. ... 

Drag-drag interactions Etravirine is metabolized by cytochrome P450 enzymes and interacts in vitro with high-dose ritonavir, atazanavir, fosamprenavir, rifampicin, and some antiepileptic drugs [159 ]. 

Drug-drug iuteractious Atazanavir -f ritonavir In a phase I, open, one-arm study, 14 HIV-seronegative volunteers first took rifampicin 600 mg/day for 8 days and then added atazanavir 300 mg bd and ritonavir 100 mg bd however, when atazanavir and ritonavir were added, the first three subjects developed vomiting and rises in aminotransferases and the study was terminated [83 ]. 

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