pentobarbital will lower the extent or effect of mifepristone by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Watch. CYP3A4 inducers have not been researched, coadministration not proposed by companyfentanyl transmucosal and pentobarbital both equally enhance sedation. Stay clear of or Use Alternate Drug. Restrict use to suffe