Case report of stuttering acquired in association with phenytoin use for post-head-injury seizures

Previous research indicates that stuttering and deficits in motor performance may be associated with the use of phenytoin (Dilantin). The present report concerns a case of stuttering acquired in association with phenytoin use for post-head-injury seizures. The extent and nature of dysfluencies and the motor performance of speech and nonspeech muscle systems were evaluated over an extended period during which changes in anticonvulsant medication were made. Reductions in dysfluency levels and improved motor performance were observed following a medication change from phenytoin to carbamazepine. Performance on tests assessing nonmotor functions, such as memory and attention, was equivalent before and after the medication change. The apparent association between dysfluency levels, motor performance deficits, and phenytoin suggest that in the present case stuttering resulted in part from a general impairment in motor control.