Understanding Pet Seizure: Causes, Symptoms, and What to Do

What are seizures? Are they dangerous?

Seizures are abnormal, uncontrolled bursts of activity in the brain that causes uncontrollable muscle activity. They are also sometimes known as convulsions or fits. 

A one-off, short seizure is typically not dangerous to a pet. However, seizures that last for more than 5 minutes, also known as status epilepticus, can quickly become life-threatening. Status Epilepticus can also cause permanent brain damage and can cause more seizures that are resistant to anti-seizure medications. Multiple (>2) short seizures within a 24 hour period (known as cluster seizures) can also have a similar effect if not treated.

What should I do if my pet has a seizure? 

 

Despite the dramatic appearance, seizures are not painful for your pet, though some may be distressed and confused. The best thing you can do is prevent your pet from falling or hitting any nearby objects, and bring your pet to a veterinarian where further diagnostics can be performed. Seizures that last more than 5 minutes can be fatal and should be treated immediately by a veterinarian. 

 

Keep the lighting low if possible, and note the time the seizure began and ended. Monitor your pet after the seizure and note any abnormal behaviours. These may provide helpful information for your vet. 

 

Contrary to common belief, dogs/cats do not tend to bite or swallow their tongue during a seizure. DO NOT place objects or your finger into your pets’ mouth during a seizure. 

 

What causes seizures? 

 

There are many causes of seizures, which can ultimately be grouped into two categories- intracranial causes, and extracranial causes. Extracranial causes are causes that originate outside the brain, such as kidney disease, liver disease, low blood sugar, toxins, imbalanced electrolytes etc. Intracranial causes are causes that originate inside the brain, such as brain tumours, brain trauma, etc. 

 

When diagnostics have been run and all major causes have been ruled out, we come to a diagnosis of idiopathic epilepsy. Idiopathic epilepsy is an inherited disorder which causes seizures, but the exact mechanism is unknown. It is considered a “diagnosis of exclusion”, which means that we can only diagnose idiopathic epilepsy by ruling out all other causes. Unfortunately, the majority of seizures are caused by idiopathic epilepsy, making the diagnostic journey frustrating for both clients and veterinarians alike. 

 

How is the cause of seizures determined?

 

Extracranial causes of seizures are typically easier and faster to rule out, so your veterinarian may start with a physical examination and a full blood test +/- a urine test. If the tests are normal and there is no history of toxin exposure, further testing for intracranial causes may be recommended depending on the severity of the seizures, such as a CT scan or an MRI. Sampling of the cerebrospinal fluid may also provide valuable information.

Are seizures treatable? 

 

The treatment of seizures depends largely on the underlying condition causing the seizures. If there is an underlying cause identified, treatment will be targeted at managing that cause. If there is no underlying cause found (idiopathic epilepsy), or the underlying cause is untreatable, then anti-seizure medications are usually started. It is important to remember that anti-seizure medications are just symptomatic treatment, meaning they may stop the seizures, but do not deal with the root of what is causing the seizures. 

 

As a one-off, short (<5 minutes) seizure event is not typically harmful to dogs, anti seizure medications are only typically started when: 

1. There are two or more seizure events in a 6 month period. 
2. There are two or more seizure events in a 24 hour period. 
3. A seizure lasts for 5 minutes or longer. 
4. There is evidence of brain damage/a tumour.
5. There is a history of prior brain disease or injury. 

 

My pet is on seizure medications, what do I need to know?

 

It is very important to note that seizure medications cannot be discontinued suddenly, as some seizure medications can cause withdrawal seizures if discontinued too suddenly. As each pet responds differently to each medication, certain seizure medications also require regular blood testing to ensure that there are adequate amounts of the drug in your pets’ blood to prevent the seizures, but not too much that side effects are seen. 

 

Seizure medications are a life-long commitment, along with regular checkups and blood monitoring. It is by no means an easy feat, however it is well worth it in the long run, as most stable idiopathic epilepsy patients go on to live long and happy lives!

 

References: 

 

1. Podell, M., Volk, H.A., Berendt, M., Löscher, W., Muñana, K., Patterson, E.E. and Platt, S.R., 2016. 2015 ACVIM small animal consensus statement on seizure management in dogs. Journal of Veterinary Internal Medicine, 30(2), pp.477-490.
2. Maintenance Anticonvulsant or antiepileptic therapy - maintenance anticonvulsant or antiepileptic therapy MSD Veterinary Manual. Available at: https://www.msdvetmanual.com/pharmacology/systemic-pharmacotherapeutics-of-the-nervous-system/maintenance-anticonvulsant-or-antiepileptic-therapy (Accessed: 27 August 2024). 
3. Seizures in dogs: VCA Animal Hospitals VCA Available at: https://vcahospitals.com/know-your-pet/seizures-general-for-dogs (Accessed: 27 August 2024). 

Done by: Doctor Hannah Lee