Behavioral effects of anticonvulsant prophylaxis: no effect or artifact?

We examined the effects that may be attributable to current use of anticonvulsants in patients with traumatic head injury. The performances of 15 head-injured matched pairs were compared on a comprehensive battery of neuropsychological and psychosocial measures 1 year post injury. The members of both groups were placed on anticonvulsants, principally phenytoin, immediately after the head injury. The members of one of the groups were still taking the drug at 1 year; the others had discontinued prior to that time. Although the results provided no evidence for appreciable side effects of anticonvulsants on formal neuropsychological or psychosocial measures, some methodological issues need to be considered in the interpretation of results and future studies of drug side effects.