pentobarbital will lessen the extent or result of guanfacine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Check Intently. Potent or average CYP3A4 inducers noticeably cut down guanfacine plasma concentrations and elimination half-lifestyle.pentobarbital will lower the level or effect of eplerenone by impacting hepatic/in