Observe Intently (one)pentobarbital will minimize the extent or influence of fentanyl by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Intently. Coadministration of fentanyl with CYP3A4 inducers could lead to some lessen in fentanyl plasma concentrations, not enough efficacy or, probably, advancement of the withdra