pentobarbital will lessen the level or effect of conivaptan by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Check.pentobarbital will reduce the level or result of fosaprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Warning/Observe.pentobarbital will minimize the level or effect of erlotinib by impacti