NisazonZonisamide (brand names include Nisazon) is a prescription anticonvulsant medication primarily used to prevent and control seizures in patients with epilepsy. It is chemically a sulfonamide derivative. Primary Use: Adjunctive therapy (used in combination with other medications) for partial onset seizures in adults and children aged 6 years and older. In some regions and cases, it is also used as a monotherapy (sole treatment).