Hypolipidemic activity of antiepileptic 5-phenylhydantoins in mice

Administration (20 mg/kg i.p.) of antiepileptic 5-phenylhydantoins phenytoin, ethotoin, mephenytoin, and selected metabolites to mice over a period of 16 days produced lower serum concentrations of cholesterol and triglycerides with most of the compounds studied. Several compounds were more effective hypolipidemic agents than clofibrate at 150 mg/kg per day. Several N-alkylated derivatives of the most active compound, 5-ethyl-5-phenylhydantoin, a metabolite of mephenytoin, displayed activities equal to those of the underivatized compound. These in vivo studies suggest that antiepileptic phenylhydantoins, when used in chronic therapy in man, could possibly act as hypolipidemic agents.