bosentan will lessen the level or effect of fentanyl by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Keep track of Carefully. Coadministration of fentanyl with CYP3A4 inducers could lead on to a reduce in fentanyl plasma concentrations, not enough efficacy or, potentially, development of a withdrawal syndrome in a very indi… Read More