Cats can have focal seizures (drooling, facial movements, excessive vocalizations, random behavior, abnormal head or neck movements) or generalized seizures characterized by tonic clonic movements. When taking the history, it is important to differentiate seizures from syncopal episodes, vestibular disease, pain, hyperesthesia, or behavioral issues. Physical examination should include careful fundic examination and neurologic evaluation, which should localize disease to the forebrain. Clinical signs of forebrain disease in cats include mentation changes, visual deficits contralateral to the lesion, facial or nasal desensitization contralateral to the lesion, anisocoria, propulsive wide circling with a normal gait toward the lesion, general proprioceptive deficits contralateral to the deficit, and possibly head and neck hyperesthesia on palpation. It is best to examine the cat after it has recovered from a seizure because the postictal phase can make interpretation of the neurologic signs difficult. Unilateral lesions are usually associated with a mass or structural lesion, whereas multifocal disease is associated with metabolic, degenerative, toxic, infectious, inflammatory, or neoplastic disease. Baseline blood analysis should be done to determine the need for metabolic examination. Advanced diagnostic tests such as magnetic resonance imaging, computed tomography, and cerebrospinal fluid analysis are also needed to rule causes in or out. Cultures and infectious disease titers of the cerebrospinal fluid may also be helpful.
Phenobarbital is the current drug of choice for cats and is used at a dosage of 2.4 mg/kg Q 12 H. Complications may include sedation, ataxia, and weight gain secondary to polyphagia, along with polyuria and polydipsia. Blood dyscrasias have been seen. Diazepam can be used as an adjunct drug if phenobarbital use is not sufficient. Bromide has been associated with idiosyncratic allergic pneumonitis and is not particularly effective. Levetiracetam is a newer drug that has been used successfully in cats with idiopathic epilepsy. Zonisamide has been used in cats but has been associated with a high frequency of adverse reactions. The newest antiseizure “drug” is pregabalin; little information about this agent is available in cats.
COMMENTARY: This is an excellent review of the clinical signs, workup, and short- and long-term management of cats with seizures. The review contains a detailed discussion on monitoring cats and withdrawal of drugs.—Karen A. Moriello, DVM, Diplomate ACVD
The seizuring cat: Diagnostic work-up and therapy. Bailey KS, Dewey CW. J FELINE MED SURG 11:385-394, 2009.