pentobarbital will lower the level or impact of atazanavir by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Small/Significance Unfamiliar.Barbiturates can induce hepatic microsomal enzymes resulting in improved metabolism and lowered anticoagulant reaction of oral anticoagulants (eg, warfarin, acenocoumarol, dicumarol, and phenprocoumon)