Butabarbital will reduce the level or impact of levonorgestrel oral/ethinylestradiol/ferrous bisglycinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Carefully. The efficacy of hormonal contraceptives may very well be reduced. butabarbital will minimize the level or influence of pioglitazone by influencing hepatic/intestinal enzyme CYP3A4 metabolis... https://douglasx468vxy2.blgwiki.com/user