pentobarbital will decrease the extent or outcome of pitolisant by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Watch Carefully. Pitolisant exposure is decreased by fifty% if coadministered with potent CYP3A4 inducers.pentobarbital decreases amounts of vandetanib by influencing hepatic/intestinal enzyme CYP3A4 metabolism. C