pentobarbital will lower the extent or effect of etonogestrel by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Warning/Monitor.pentobarbital will lessen the extent or result of cilostazol by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Keep track of.fentanyl transdermal and pentobarbital both improve sedation. S