Comparison the cognitive effect of anti-epileptic drugs in seizure-free children with epilepsy before and after drug withdrawal

We studied the cognitive effects of antiepileptic drugs (AED), by investigating epileptic children who were seizure-free for at least 2 years and who had undergone fixed monotherapy. Seventy consecutive epileptic children (25 with carbamazepine (CBZ), 22 with phenobarbital (PB), and 23 with valproate (VPA)) were examined by Wechsler Intelligence Scale for Children-Revised (WISC-R) and auditory event-related potentials (P300) at three sessions: before AED reduction, then 1 and 7 months after complete withdrawal of treatment. There were no significant differences in IQ and subtests scores of WISC-R in any group at any of the three sessions. P300 latencies were significantly increased in the children receiving PB but not in children receiving CBZ or VPA. P300 amplitudes were increased but not significantly different among the three groups. These findings suggest that PB may affect cognitive function on children, but the changes of P300 latencies may improve after discontinuation.