Induction of epileptic negative myoclonus by oxcarbazepine in symptomatic epilepsy

Provocation of various seizure types including epileptic negative myoclonus and generalised atonic seizures is rarely observed in children treated with carbamazepine (CBZ). Provocation of the latter seizure types by oxcarbazepine (OXC) is not described in the literature. We report a four-year-old boy with symptomatic epilepsy caused by left-sided cerebral atrophy of unknown origin who developed numerous daily drop attacks when exposed to OXC. Polygraphic analysis revealed secondary generalised precentral sharp-slow waves frequently associated with a silent period lasting for 100-150 ms in the electromyogram recorded from the deltoid and neck muscles. These seizures stopped promptly within 36 hours after discontinuation of OXC. This case demonstrates that OXC, similar to CBZ, can provoke epileptic negative myoclonus in some children with focal epilepsies. [Published with videosequences].