Proton pump inhibitors Indinavir

Drugs that may affect atazanavir include the following antacids and buffered medications, clarithromycin, didanosine (buffered formulation only), efavirenz, H2-receptor antagonists, indinavir, itraconazole, ketoconazole, nevirapine, proton pump inhibitors, rifampin, ritonavir, St. John s wort, tenofovir, voriconazole. 

Clinically important, potentially hazardous interactions with bepridil, cisapride, dasatinib, dofetilide, ergot derivatives, etravirine, fentanyl, fesoterodine, garlic, indinavir, irinotecan, ixabepilone, lapatinib, lovastatin, marihuana, midazolam, pimozide, proton-pump inhibitors, raltegravir, rifampin, ritonavir, sildenafil, simvastatin, solifenacin, St John s wort, temsirolimus, triazolam... 

Atazanavir Atazanavir is a peptide protease inhibitor that is active against both HlV-1 and HlV-2. Absorption is increased by food and it is recommended that the drug be administered with a meal. Absorption may be pH dependent, because proton pump inhibitors substantially reduce drug concentration after oral dosing. Like indinavir, atazanavir frequently causes unconjugated hyperbilirubinemia. The drug may be less likely than other HIV protease inhibitors to cause lipodystrophy. 

Proton pump inhibitors (marked effect) and H2-receptor antagonists (modest effect) reduce atazanavir levels. Other drugs that increase gastric pH are also predicted to reduce plasma levels of atazanavir. Fosamprenavir may be similarly affected (moderate effects seen with ranitidine), although antacids and esomeprazole had little effect in one study. Omeprazole decreases indinavir levels and an antacid modestly decreased tipranavir levels. Neither ranitidine nor omeprazole had any effect on darunavir/ritonavir or lopinavir/ritonavir levels. In contrast, cimetidine, ranitidine and omeprazole have been shown to increase saquinavir levels. 

The interaction between omeprazole and indinavir would appear to be established. Omeprazole should probably not be used with indinavir unless ritonavir is used to boost the indinavir levels. This would likely apply to other proton pump inhibitors used with indinavir as well. 

Burger DM, Hugen PWH, Kroon FP, Groeneveld P, Brinkman K, Foudraine NA, Sprenger H, Koopmans PP, Hekster YA. Pharmacokinetic interaction between the proton pump inhibitor omeprazole and the HIV protease inhibitor indinavir. AIDS (1998) 12, 2080-2. 

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