Seizures are a sudden surge of electrical activity in the brain that can occur for a number of different reasons. In most cases, during this surge in electrical activity, spontaneous uncontrolled movements (such as trembling, leg paddling and twitching) occur as well as changes in consciousness or behavior. Often, a pet may salivate excessively and lose control of their bladder or bowel.
After a seizure, it is common for a pet to seem disorientated and visually impaired (sometimes blind) for a period of a few minutes to a few hours.
What Causes Seizures?
Seizures are either caused by a problem in the brain (such as trauma, infection, epilepsy or tumors) or by factors outside the brain (such as low blood sugar, toxins, poisons or diseases such as hypothyroidism in dogs).
Your veterinarian will first want to rule out the causes outside of the brain. This requires blood testing (and other tests such as urinalysis) and understanding the full history of your pet including the possibility of them accessing poisons or chemicals. If these tests are negative, then your veterinarian will make a decision on whether further diagnostic tests such as an MRI scan, CT scan or cerebrospinal fluid analysis are indicated.
In cats and dogs less than a year old, it is common for infection to be involved. In older patients (over the age of 5), there is greater potential for a tumor to be involved. In pets aged one- to five-years-old, often no cause is found and the term “epilepsy” or “idiopathic epilepsy” is used to refer to the seizure(s). If seizures occur frequently, medication can be used to help suppress them from occurring.
Epilepsy is more commonly diagnosed in dogs than cats (usually a cause is found for the seizures in cats).
When Is A Seizure An Emergency?
Seizures are an emergency when:
- Seizure activity is non-stop for 3 - 5 minutes or more (a condition called status epilepticus)
- 2 or more seizures occur in a 24 hour period
However, as a rule, it is best to call your veterinarian whenever a seizure occurs to seek their advice.
How Are Seizure Disorders Treated?
Seizures are a symptom and so it is important to treat the underlying condition that causes them.
In cases of idiopathic epilepsy (where no underlying cause is identified and the patient is normal between seizures), the most common drug used is phenobarbital (a barbiturate).
After starting the drug, it takes a few weeks for the blood levels to reach a level that causes suppression of seizures, and regular blood testing is required to ensure this level is maintained (usually every 6 months or sooner if seizures start again).
Other drugs such as Potassium Bromide can be added if seizures remain uncontrolled.
Liver function tests are usually performed once or twice a year, as phenobarbital can be harmful to the liver. Side effects of phenobarbital are sedation and increased appetite / thirst.
Can Seizure Medication Be Stopped?
This may be appropriate for some patients and should be discussed with your veterinarian (typically, if no seizure activity has occurred for a year or more). Withdrawal of the drug should be gradual if this is attempted.
Although we all love our animals and hate to see them suffering, remember that pets can be distressed during and after a seizure. Please be careful for your own safety.