Canine Idiopathic Epilepsy: What it is, Causes, Treatments, and More

Dr. Ailsa Rutherford
4 min readJul 27, 2022


Photo by Shaq Hossain on Unsplash

What is canine idiopathic epilepsy?

Canine idiopathic epilepsy is a chronic disease in dogs characterised by seizures with an unknown cause. Seizure disorders are generally considered idiopathic if, aside from the seizures, the dog has no brain abnormalities and no other cause within the body.

Epileptic seizures are ultimately caused by abnormal, excessive synchronous neuronal activity in the brain. Dogs must experience at least two unprovoked seizures 24 hours apart to be classified as epilepsy. Epilepsy in dogs is typically a lifelong condition; only six to eight percent of dogs diagnosed will go into remission and no longer require ongoing treatments.

What causes it?

For a disease or condition to be idiopathic, it must have an unknown cause or arise spontaneously. Although there is strong evidence that some genetic component causes this disease, the specific genetic variants have remained elusive. Since canine idiopathic epilepsy is hereditary, dogs with this condition should not be bred.

What are the symptoms of canine idiopathic epilepsy?

Epilepsy can cause dogs to suffer from three categories of seizures: focal, generalised, and focal-to-general. Each category of seizures is characterised by how it affects the animal’s brain and its unique symptoms.

Focal Seizures

Focal seizures only affect one half of the brain at a time and are localised to a small zone within that half. The symptoms your dog experiences will be directly related to which side of the brain and what region the seizure is in.

  • Seizures in the motor region of the brain can cause unusual involuntary movements such as paddling or kicking of one limb, repeated eye blinking, facial twitching, chewing movements, or head shaking with a loss of consciousness.
  • Seizures in the autonomic nervous system can cause symptoms such as vomiting, dilated pupils, and excessive salivation, but no loss of consciousness.
  • Focal seizures in other areas of the brain can cause unusual psychological behaviours such as unexplained fear, general anxiety, and restlessness.

Generalised Seizures

Generalised seizures, unlike focal seizures, occur on both sides of the brain simultaneously, causing both sides of the body to be affected. It is common for dogs to lose consciousness and even lose control of their bladder and or bowels. Generalised seizures are identified through five subcategories based on their symptoms and how the body is affected.

  • Atonic seizures, also known as drop attacks, feature a sudden and complete loss of muscle function, usually leading to collapsing and loss of consciousness.
  • Tonic seizures cause mass muscle stiffening, where the back, legs, or core can become locked up for anywhere between a few seconds and several minutes.
  • Clonic seizures are where the muscles rapidly and repeatedly contract, causing a jerking/paddling motion of the legs.
  • Tonic-Clonic seizures begin as a tonic seizure will classic muscle stiffening and immediately follow into clonic muscle contractions and jerking motions.
  • Myoclonic seizures can be similar to clonic seizures but are characterised by sporadic jerking on both sides of the body and no loss of consciousness.

Focal-to-Generalized Seizures

One of the most common seizure types in dogs begins as focal and then evolves into a generalised seizure. Because the focal portion of the seizure can go unnoticed by pet owners, it is important to think back to just before the generalised seizure and know the symptoms of a focal seizure. Being able to differentiate between a generalised seizure and a focal to generalised seizure is important to treat your dog.

How is it diagnosed?

Canine idiopathic epilepsy is typically diagnosed after other diseases, and conditions that can cause seizures are ruled out. Performing a complete blood count, biochemical analysis, and urinalysis can rule out systemic diseases. Magnetic resonance imaging (MRI) is often used to eliminate the possibility of brain anomalies such as unusual inflammation, brain lesions, or tumours.

How is canine idiopathic epilepsy treated?

Like most medical conditions, canine idiopathic epilepsy is treated based on various factors. The seizure type, severity and frequency, and potential side effects of medication are all in question before beginning treatment.

Finding the best treatment option depends on the benefit vs risk ratio, patient assessment, and the owner’s personal and financial commitments. It’s important to know that canine idiopathic epilepsy is not curable, and treatment typically manages the condition.

Antiepileptic Medications

Years ago, phenobarbital and potassium bromide were the go-to medication for managing epilepsy due to their successful history, low cost, and availability. More recently, however, there are many options for managing your dog’s seizures, and there is no evidence showing anyone antiepileptic to be more effective than the rest.

Although they were initially developed for treating epilepsy in people, many of the antiepileptic medications of the last 20 years are safe for animals as well. It is typically ideal to find a single effective drug rather than a combination of several medications, which is more complicated for pet owners.

Natural Options

For pet owners who don’t love the idea of medicating their dog or for dogs who don’t respond well to traditional medications, there are plenty of natural options to try. The most common can include food therapy, Chinese herbal formulas, acupuncture, and hemp (CBD) oil.

Using hemp (CBD) oil to prevent and reduce seizures is a relatively new practice but has displayed promising results in numerous studies. In addition to the nutritional boost of essential fatty acids and antioxidants, hemp oil works with the body’s endocannabinoid system to regulate several bodily functions.

Regarding seizure activity, hemp (CBD) oil can reduce the frequency and severity of seizures, even in dogs with drug-resistant epilepsy. When studied as a treatment for epilepsy in dogs, Colorado State University found that 89% of dogs receiving the hemp oil had a reduction in seizures.

Additionally, human and veterinary literature suggests hemp oil supports the immune, nervous, gastrointestinal, and cardiovascular systems and reduces seizure activity, pain, and anxiety.

For more information on the benefits of hemp (CBD) oil, please read our Ultimate Guide to CBD Oil for Pets.



Dr. Ailsa Rutherford

Senior practicing veterinarian. Member of the Australia and New Zealand College of Veterinary Surgeons in Emergency. Head of Animal Health at Buddy Pet P/L.