Abstracts

Rationale: Cenobamate is one of the newest anti-seizure medications (ASM), which has yielded seizure freedom in approximately 20-25% of patients suffering from treatment resistant focal epilepsy. Forced normalization (FN) is a rare phenomenon that affects approximately 1% of patients with treatment resistant epilepsy and consists of the development of de-novo psychosis and /or severe mood disorder and /or behavioral disorder following the remission of seizures in these patients. In this case report, we present a patient who developed FN following the start of cenobamate.

Methods: A 35-year-old Caucasian male patient with a history of treatment-resistant focal epilepsy and autism spectrum disorder with moderately severe intellectual disability was started on cenobamate and developed insomnia, severe agitation with aggressive behavior and self-harming behavior after reaching a dose of 50mg daily.

Results:
The patient had become seizure free for 42 days while on cenobamate, after which his family reported the psychiatric symptoms. Cenobamate was discontinued which resulted in remission of his psychiatric symptoms. At the same time his seizures recurred at his previous baseline frequency of 2-3 per month. Of note, previous trials with valproic acid, lamotrigine, and zonisamide were associated to aggressive behavior but not as severe as those reported on cenobamate.




Conclusions:
The data presented in this case report could suggest the possibility of the FN phenomenon, given the remission of seizures for 42 days after the introduction of cenobamate associated with the development of severe psychiatric disturbances which remitted with the recurrence of seizures. To our knowledge, this is the first case reported of such a condition with this ASM. However, we cannot totally exclude the possibility that the psychiatric phenomena were the expression of iatrogenic psychiatric symptoms caused by this ASM.




Funding: No funding was involved in this abstract