Microseizures Induced by Topiramate.

A 22-year-old Japanese male with trisomy 21 was diagnosed with West syndrome at 4 months old. After the suppression of epileptic spasms using adrenocorticotropic hormone therapy, he had complex partial seizures and bilateral frontal epileptic discharges on EEG. Although the introduction of topiramate (TPM) decreased the seizures during wakefulness, frequent episodes of brief eye-opening appeared during sleep while the patient was taking TPM (400 mg/day). EEG showed fast activity at the times of eye-opening. The episodes of eye-opening during sleep and the fast activities disappeared upon TPM discontinuation. This is the first report of TPM-induced microseizures similar to benzodiazepine-induced microseizures.