pentobarbital will lower the level or effect of darunavir by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.pentobarbital will decrease the extent or impact of guanfacine by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Check Closely. Powerful or reasonable CYP3A4 inducers considerably cut dow