Feline Epilepsy

Epilepsy is a brain disorder that causes sudden, uncontrolled physical episodes called seizures. Cats may be fully conscious or lose consciousness during these episodes, and they tend to recur over time. When there's no identifiable underlying cause, it's referred to as idiopathic epilepsy.

Cats often show a brief warning phase before a seizure begins, called a focal onset. This is when abnormal electrical activity starts firing in one or more areas of the brain. During this time, your cat may look confused or frightened, and may seek you out for comfort or go hide.

Once the seizure itself begins - which typically lasts up to about 90 seconds - your cat will usually fall to their side. During the seizure, they may urinate, defecate, paddle all four limbs, chomp their jaw, stiffen, vocalize, or drool excessively.

Seizures most often happen while a cat is resting, commonly at night or in the early morning. By the time you get your cat to the vet, most of the visible signs will likely have passed, which is why timing and describing what you saw matters so much for diagnosis.

Most cats with epileptic seizures are between one and four years old. Afterward, cats often go through a recovery period called the postictal phase, which can include confusion or clumsiness, compulsive behavior, pacing, wandering without apparent direction, temporary loss of sight, increased appetite (polyphagia), and increased thirst (polydipsia). Recovery time varies - some cats bounce back almost immediately, while others take a full day to return to normal.

In most cases, the underlying cause of feline epilepsy isn't identified. Some idiopathic cases do appear to have a genetic component.

Two key factors help determine whether a cat's epilepsy is idiopathic: the age at which seizures first began, and the frequency and pattern of the seizures.

If a cat has two or more seizures within the first week of onset, your veterinarian will typically look beyond idiopathic epilepsy toward another underlying cause. Seizures that begin in cats younger than one or older than four raise suspicion for a metabolic issue or an intracranial (within-the-skull) cause. Focal seizures in particular often point toward a structural issue in the brain rather than idiopathic epilepsy.

Diagnosis usually starts with routine bloodwork, including a complete blood count, thyroid screen, and blood chemistry profile. Your vet will also typically test for viral infections such as feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV), along with a urinalysis. Depending on the findings, further testing - such as an MRI, CT scan, or spinal tap - may be recommended to pin down the cause.

Careful monitoring is a key part of long-term management. Cats on phenobarbital need periodic blood testing to check serum drug levels and overall organ function - how your cat responds, along with those blood levels, will guide any dosage adjustments.

Potassium bromide is generally not recommended as a maintenance anticonvulsant in cats. A significant portion of cats can develop a severe, sometimes fatal asthma-like lung condition in response to the drug. Your veterinarian will choose anticonvulsants that are safer and more appropriate for feline patients.

If your cat has other health conditions, particularly involving the liver or kidneys, this may influence which anticonvulsant your vet recommends and how closely they'll want to monitor bloodwork over time.

It's generally recommended that cats with genetic or idiopathic epilepsy be spayed or neutered to avoid passing the trait on to future litters.

Never give your cat any over-the-counter medication without checking with your veterinarian first. Some common medications can interact with anticonvulsants or lower the seizure threshold, increasing the risk of more frequent seizures.

Consistency matters a great deal with anticonvulsant medication. Try not to miss doses, and keeping your cat indoors can help ensure they're always available for their scheduled medication.

When epilepsy has a genetic or hereditary basis, there's little that can be done to prevent it outright. What matters most is consistent treatment - suddenly stopping anticonvulsant medication can make seizures worse or more frequent, so any changes to your cat's treatment plan should always go through your veterinarian.