pentobarbital will reduce the level or impact of mifepristone by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Watch. CYP3A4 inducers have not been examined, coadministration not advised by companypentobarbital will minimize the extent or influence of etravirine by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use