pentobarbital will lower the extent or effect of fosphenytoin by impacting hepatic enzyme CYP2C9/ten metabolism. Use Warning/Check.pentobarbital will lessen the level or effect of alfuzosin by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Slight/Significance Not known.fentanyl iontophoretic transdermal process and pentobarbital both boos