Anticonvulsant therapy and its possible consequences on peripheral nervous system: a neurographic study.

We studied 80 epileptic patients receiving antiepileptic drugs in mono- or polytherapy. For every patient, peroneal and median nerve motor conduction velocities and median nerve sensory conduction velocity were calculated. The average conduction velocity values were remarkably slower than those of a group of 55 normal subjects. We found at least one abnormal conduction velocity value in patients treated with carbamazepine (CBZ), phenobarbital, and phenytoin. There was no specific prevalence of one of these drugs. We found a noticeable relationship between conduction velocity slowing and daily dosage for CBZ only. There was no relationship between conduction velocity slowing and drug blood levels or duration of treatment.