Seizures in cats are caused by active structural disease or secondary epilepsy. The most common structural causes are inflammatory diseases, many of which are probably viral (non-FIP) in origin. Toxoplasmosis, FIP, FeLV, and FIV are rare causes of recurrent seizures in cats. The incidence of primary epilepsy is unknown; it is unlikely to occur in domestic cats. The pattern (type and frequency) of the seizures and the age at onset of the seizures are important factors in establishing a differential diagnosis. More than 50% of cats with seizures experience nonconvulsive (mild generalized or partial complex) seizures. Though many cats experience severe cluster seizures and status epilepticus, severity of seizures is not a good predictor of outcome. Many cats stop having seizures or are controlled well with AEDs regardless of the severity of their seizure activity.