Psychosis induced by zonisamide: a case report and review of the literature.

Zonisamide is an anti-seizure medication that is indicated for adjunctive therapy in the treatment of partial seizures. This medication is rarely used in the United States. An infrequent adverse effect of psychosis occurs in about 2% of patients taking zonisamide. This is a case report of a 34-year-old male on phenytoin who presented with psychosis symptoms approximately 10 months after starting adjunctive zonisamide.