pentobarbital decreases levels of elvitegravir/cobicistat/emtricitabine/tenofovir DF by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Might cause loss of virologic reaction and probable resistance.pentobarbital will decrease the extent or result of imatinib by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Minima