Zonisamide is a capsule prescribed by veterinarians to help reduce the symptoms of epilepsy-caused seizures in animals. Depending on your pet's condition, seizures can probably be treated with Zonisamide by itself or as part of a combination of other seizure-treating medications. It can be used to help treat both cats and dogs. It usually takes effect in 2-4 hours following administration. Compared to other seizure-treating medications, Zonisamide features fewer side effects, so be sure to ask your veterinarian if this is the right medication for your pet's case.