pentobarbital will lessen the extent or result of fentanyl intranasal by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Keep track of Carefully. Coadministration of fentanyl with CYP3A4 inducers may lead to a lessen in fentanyl plasma concentrations, not enough efficacy or, perhaps, improvement of the withdrawal syndrome in t