pentobarbital will reduce the level or impact of atazanavir by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Small/Importance Unidentified.Barbiturates can induce hepatic microsomal enzymes causing improved metabolism and decreased anticoagulant response of oral anticoagulants (eg, warfarin, acenocoumarol, dicumarol, and phenprocoumon); pa