HIVers taking protease inhibitor Reyataz shouldn’t take proton-pump inhibitors (PPIs), stomach meds like Prilosec (omeprazole): The PPIs cause the PI levels to fall too low. • Pregnant women shouldn’t use Crixivan—the first PI crossed off the preggers list. • Taking the antibiotic rifampin (it fights staph, TB and other infections) with Norvir-boosted Invirase can damage your liver.