pentobarbital will decrease the level or influence of pitolisant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Check Closely. Pitolisant exposure is diminished by 50% if coadministered with solid CYP3A4 inducers.pentobarbital will lower the extent or impact of estropipate by influencing hepatic/intestinal enzyme CYP3A4 me