pentobarbital will lower the extent or impact of atorvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Watch.pentobarbital will lower the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Keep track of Intently. Coadministration of fentanyl with CYP3A4 indu