Check Intently (1)phenobarbital will decrease the extent or impact of fentanyl transmucosal by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Keep track of Intently. Coadministration of fentanyl with CYP3A4 inducers could lead to your lower in fentanyl plasma concentrations, deficiency of efficacy or, possibly, enhancement … Read More