pentobarbital will reduce the extent or result of methadone by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.pentobarbital will lessen the level or result of norgestrel by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Keep track of Carefully. Average CYP3A4 inducers may perhaps lessen progestin