Zonisamide

Zonisamide (Zonegran) is a sulfonamide-derivative anticonvulsant that blocks sodium and calcium channels, reducing abnormal neuronal firing. It is FDA-approved as adjunctive therapy for the treatment of partial-onset seizures in adults with epilepsy. Because zonisamide contains a sulfonamide moiety, it should be used with caution in patients with a sulfa allergy, and it carries risks of kidney stones, metabolic acidosis, and reduced sweating (with risk of heat-related illness), so adequate hydration and monitoring are recommended, especially in hot climates or with strenuous activity.