Health Topics  >  Neurological  > Seizures

What causes seizures in dogs?

There are numerous things that could potentially cause a seizure in your dog. You’ll need to see your vet to determine the underlying cause through a proper diagnosis. Although not a comprehensive list, the following causes have been linked to canine seizures:


Toxins or Poisoning

There is a long list of toxins that can cause seizures in dogs. Common medications that may cause seizures (especially if an overdose occurs) include Ibuprofen, Ivermectin, Phenylbutazone, Diphenhydramine, and Fluoroquinolone antibiotics, just to name a few.

Some plants can also cause seizures in dogs. Examples of these include Sago palm, Castor Bean, and Cyclamen. Common human foods can also be responsible for causing seizures in dogs. Examples of these include foods containing Xylitol, mushrooms, grapes, chocolate, caffeine, and nutmeg.


Seizures can be inherited. Breeding dogs who have signs of epilepsy should be tested. If the results are positive, the dog should not be used for breeding. Idiopathic epilepsy, the most common type of seizures in the dog, is an inherited disorder, but its exact cause is unknown.

Injuries to the Brain

A brain tumor has the ability to cause seizures in dogs. Seizures may also occur if the brain suffered a trauma that causes inflammation.


An untreated infection in the nervous system or in the brain can potentially cause seizures in dogs. A viral infection like distemper causes fluctuations in the brain’s electrical activity, which will lead to seizures if not treated.

Heat Stroke

When a dog is unable to lower their body temperature, heat stroke can occur. Severe heat stroke can cause seizures in some dogs.

Organ Diseases

Dogs who suffer from liver or kidney disease may also have seizures. When these organs are not filtering toxins and waste properly, this allows high levels to build up, commonly producing seizures.


Infestations of worms can also cause seizures. When heartworms, tapeworms, roundworms, or hookworms are present in significant numbers, they can potentially damage the nerves which could interfere with proper transmission of electrical signals to the brain.

Low Blood Calcium

This is especially dangerous in nursing mothers because calcium plays a vital role in regulating electrical activity in the brain. When calcium levels fall too low, this can disrupt proper brain function and ultimately lead to seizures.

Low Blood Sugar

When blood sugar levels drop significantly and remain low, the brain is not getting the sugar it needs to function normally. This can trigger electrical fluctuations that may cause seizures.


Sometimes ruling out other causes requires advanced diagnostics like MRI and spinal taps, but not always pursued as they are invasive and costly procedures. In these cases, idiopathic epilepsy is often a “presumptive diagnosis”, meaning that the cause is unknown. It is diagnosed when other types of seizures have been ruled out. This type of seizure most often happens to dogs who are between six months old and six years old. 

Any breed could potentially suffer from this type of seizure but there are certain breeds in which it is more common, including German Shepherds, Border Collies, Beagles, and Labrador and Golden Retrievers. This is the most common cause of seizures in dogs.