Seizures in Cats

What is a seizure?

A seizure is also known as a convulsion or fit. It may have all or any combination of the following:

1. Loss or derangement of consciousness

2. Contractions of all the muscles in the body

3. Changes in mental awareness from unresponsiveness to hallucinations

4. Involuntary urination, defecation, or salivation

5. Behavioral changes, including not recognizing the owner, viciousness, pacing, and running in circles

What are the three phases of a seizure?

Seizures consist of three components:

1. The pre-ictal phase, or aura, is a period of altered behavior in which the pet may hide, appear nervous, or seek out the owner. It may be restless, nervous, vocalizing, shaking, or salivating. This may last a few seconds to a few hours. 
 

2. The ictal phase is the seizure itself and lasts from a few seconds to about five minutes. During this period, all of the muscles of the body contract strongly. The pet usually falls on its side and seems paralyzed while shaking. The head will be drawn backward. Urination, defecation, and salivation often occur. If it is not over within five minutes, the pet is said to be in status epilepticus or prolonged seizure. 
 

3. During the post-ictal phase, there is confusion, disorientation, salivation, pacing, restlessness, or temporary blindness. There is no direct correlation between the severity of the seizure and the duration of the post-ictal phase. 
 

Is the pet in trouble during a seizure?

Despite the dramatic signs of a seizure, the pet feels no pain, only bewilderment. They do not swallow their tongues. If you put your fingers into its mouth, you will not help your pet and you run a high risk of being bitten very badly. The important thing is to keep the pet from falling and hurting itself. As long as it is on the floor or ground, there is little chance of harm occurring. If seizures continue for longer than a few minutes, the body temperature begins to rise. If hyperthermia develops secondary to a seizure, another set of problems may have to be addressed.

What is epilepsy?

Seizures and epilepsy are less common in cats than dogs. They are, however, the most common sign of disease affecting the front part of the brain in the cat.

Seizures often occur at times of changing brain activity such as during phases of sleep, excitement or feeding. Affected cats can appear completely normal between seizures. Many different diseases can lead to seizures so it is important that diagnostic tests are performed to discover the underlying cause of the seizures. Treatment of the underlying disease is most likely to lead to successful control of the seizures. In cats, idiopathic or non-specific epilepsy, which occurs commonly in dogs, is rare.

How can I help my veterinarian to diagnose epilepsy?

By carefully observing your cat during a seizure, you can provide valuable information to your veterinarian about the types of disease that may be causing the problem. Information about your cat's lifestyle and history may also be important, including:

• What age did the seizures begin and are they getting worse?

• Are the seizures intermittent or did they develop suddenly?

• What is the frequency and duration of seizures?

• Are there any associations of seizures with sleep, excitement, feeding, etc.?

• Are there any other signs of illness such poor appetite, excessive drinking, reduced exercise, etc?

• Has the cat received any medications recently, especially deworming or flea control products?

• What diet and nutritional supplements are given?

• Has there been any access or exposure to poisons or toxins? 

Both diseases that involve the brain directly (intracranial) and conditions that affect other body systems (extracranial), especially liver or kidney disease, can cause seizures. With recent developments in treatment, many diseases that were previously untreatable may now be treated, although this can require referral to a specialist center. 

How can the cause of the seizures be diagnosed?
A range of tests is often needed before a final diagnosis can be made. Initially, this is likely to involve blood samples to look for extracranial causes. Following this a general anesthetic may be required to allow x-rays of the skull to be taken and the fluid that surrounds the brain (cerebrospinal fluid) sampled. In order to actually look at the brain, powerful imaging techniques are required. Magnetic resonance imaging (MRI) and computer-assisted tomography (CT) are the most commonly performed diagnostic tests. These tests are only available at a limited number of specialist centers.

How are the seizures treated?
It is important that a cat having regular seizures (more than one every six to eight weeks) receives treatment even if the cause is not understood, because each seizure can lead to further brain damage and increase the likelihood of more severe seizures and complications. In cases where the cause of the convulsions is unknown or is untreatable, the seizures will need to be treated directly. A variety of treatments are available. The treatment chosen will depend on each individual case and specific needs. Several changes of drug dose, frequency and type of drug may be required before the regime that suits your cat best is found. This can be a frustrating time but finding the right treatment is important for your cat’s long-term well-being. Even with treatment it may not be possible to completely prevent seizures. In many cases the aim is to reduce the seizures so your cat can lead a more or less normal life.

Golden rules of seizure treatment
ALWAYS follow the instructions on the label. Both the dose and timing of the medication are important to maintain adequate drug levels in the bloodstream.

NEVER run out of the medication as sudden withdrawal of treatment can lead to serious seizures.

INFORM your veterinarian when your supply is running low so a refill prescription can be arranged. This is particularly important if the treatment needs to be ordered specially for your cat.

KEEP these drugs safe and away from children, as they can be powerful sedatives.

BE CAREFUL about other medications, including herbs and supplements, that you give your cat. If in doubt, check with your veterinarian before giving your cat anything.

What are the side effects of treatment?

Mild side effects are common, particularly at the beginning of treatment or following changes in the regime. The most common side-effect is sedation or lethargy but other signs can also occur, most disappear quite rapidly as the cat becomes used to the medication. If side effects persist or seem severe, the veterinary practice should be informed.

DO NOT CHANGE THE DOSE OR TIMING OF MEDICATION WITHOUT CONSULTING YOUR VETERINARIAN FIRST

Why is my cat still seizuring after we started the medication?

Sometimes treatment will appear to have failed, especially during the first month or two. In many cases this is because the dosage and timing of the medication is not yet right. Please check that you are following the instructions on the medication label correctly. In some cases your veterinarian may take a blood sample to ensure that your cat has adequate circulating blood levels of the medication.

Other causes of treatment failure include:

1. Specific circumstances such as stress - increased medication may be required during such periods.

2. Progression or worsening of the disease.

3. Some cases are uncontrollable even with medication.

Seizures in cats are generally a sign of fairly severe disease; however, this does not mean that nothing can be done for your cat. With the correct treatment, the quality of your cat's life can often be dramatically improved.