The effect of sodium valproate (VPA) on learning and behavior problems in 8 children with EEG epileptiform discharges but without clinical seizures was determined in a randomized, bouble-blind, crossover study at Children’s Hospital, McMaster University, Hamilton, Ontario, Canada. Neuropsychological testing under video EEG and parent and teacher Behavior Check List (Achenbach) were applied during each treatment and placebo phase. The VPA mean trough level was 669 mcmol/L (range 251-1335).
Clinically, none of the children improved with VPA therapy. VPA reduced performance on verbal memory tasks, increased distractibility, increased delays on attentional tasks, and increased parent reports of internalizing problems. The use of VPA in patients with paroxysmal EEGs but without clinical seizures is not supported. 
COMMENT. Valproate may have adverse effects on learning, memory, and behavior in children with attention deficit and school problems who are treated because of epileptiform discharges on EEG but no clinical seizures. The decision to use AEDs in a patient with ADHD and abnormal EEG is controversial. Carbamazepine may sometimes benefit comorbid symptoms of temper outbursts and episodic confusion. However, an abnormal EEG alone is not sufficient for a diagnosis of epilepsy. Video EEG telemetry may be required to classify the symptoms as epileptic. The potential adverse effects of AEDs on learning and behavior must be weighed against possible benefits (see Ped Neur Briefs Oct 2000).