Observe Carefully (1)pentobarbital will minimize the extent or impact of fentanyl by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Check Intently. Coadministration of fentanyl with CYP3A4 inducers could lead on to your reduce in fentanyl plasma concentrations, not enough efficacy or, possibly, enhancement of a withdrawal syn