Monitor Closely (1)pentobarbital will lower the extent or impact of levamlodipine by influencing hepatic/intestinal enzyme CYP3A4 metabolism.pentobarbital will lessen the extent or effect of etravirine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Warning/Observe.pentobarbital decreases effects of hemin by pharmacodynamic antagonism. Use Wa