Subnormal Serum Folate Due to Anticonvulsive Therapy

Abstract

IN a previous study the present authors¹confirmed the numerous reports of a high frequency of subnormal serum folates (SF) in patients with epilepsy treated with diphenylhydantoin, phenobarbital, and primidone. The clinical importance of these drug-induced subnormal SF levels is unknown. Reynolds²and Strachan and Henderson³have put forward the hypothesis, that folate deficiency may lead to neuropsychiatric disorders. Reynolds²observed an improvement in the mental state and a corresponding increase in fit frequency in patients during folic acid administration, whereas Hawkins and Meynell⁴found folic acid treatment to cause a decrease in fit frequency. Horwitz et al,⁵in a controlled study, did not observe any effect of folic acid administration in respect to peripheral neuropathy in patients with subnormal SF levels due to anticonvulsant drugs. The aim of the present study has been to investigate in patients suffering from epiledsy and with drug-induced