pentobarbital will decrease the level or impact of atazanavir by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Slight/Significance Mysterious.Barbiturates can induce hepatic microsomal enzymes causing elevated metabolism and diminished anticoagulant reaction of oral anticoagulants (eg, warfarin, acenocoumarol, dicumarol, and phenprocoumon)