Seizures in Dogs: Causes, Symptoms, and Treatments

One in every 125 dogs will have a seizure this year. What causes these seizures will vary from dog to dog, with some episodes signaling an emergency, such as poisoning or head trauma, and others seemingly happening without reason.

Do you know what to do if your dog has a seizure?

Keep reading to find out the various causes of seizures and epilepsy and to learn how to identify seizures in dogs. We’ll also discuss different treatment options available for epileptic dogs and the steps you can take to improve the life of a seizure-prone dog.

Causes of Seizures In Dogs

Just as in humans, seizures in dogs are caused by sudden, uncontrolled electrical activity in the brain. This activity typically results in abnormal muscle movements and behaviors.

The causes of seizures can vary. Often, the cause may be difficult to identify, such as a genetic disorder or metabolic disease. Other times, the cause is readily identifiable by looking at the dog or running some simple tests, such as with trauma or exposure to toxins.

The causes behind seizures in dogs can be boiled down to four main categories: genetics, infection, disease, and exposure.

Genetics

Epilepsy, which is defined as the sudden, recurrent disruption of normal brain activity, is often associated with inherited abnormalities. In dogs, 10 separate genes have been identified that appear to determine a dog’s risk of various forms of inherited epilepsy. Many more forms of this disease are thought to exist, but the genetic markers for these have been more difficult to identify. When the specific cause of the seizures cannot be pinpointed through blood work or genetic testing, the condition is known as idiopathic epilepsy.

Immune-mediated brain disease, which involves inflammation of the brain or spinal cord caused by autoimmune activity, is another common genetic cause of seizures in dogs. Unlike genetic epilepsy, where seizures are the primary symptom, dogs with this condition typically suffer seizures as a secondary symptom of inflammation in the brain or brain stem.

Seizures can also be the result of malformation of the brain during development. This malformation can be caused by genetic components or environmental influence, especially in utero. Small dog breeds are most likely to suffer from these conditions, though they can affect breeds of any size.

Infection

Infections caused by bacteria, viruses, and parasites can also cause seizures in dogs. 

Any illness that causes a high fever can result in seizures. Even in the absence of fever, a bad urinary tract infection or other infection that causes inflammation can result in seizure activity in canines.

The most common infectious cause of seizures in young dogs is distemper. Bacterial sepsis is also very likely to cause seizures in puppies and adult dogs alike.

Canine Anaplasmosis, a disease carried by deer ticks, is the most likely tick-borne illness to cause seizures in dogs. However, many similarly transmitted illnesses can result in high fevers that may lead to seizure activity. Large heartworm loads and infection with Toxoplasma and Neospora parasites can also cause canine seizures.

Disease

Noninfectious diseases can also lead to seizures in pets. In fact, the second most common cause of reactive seizures in dogs is hypoglycemia or low blood sugar. A number of diseases and disease treatments can cause hypoglycemia, with metabolic disorders being the most likely culprits.

Seizures are also a symptom of uncontrolled thyroid disorders and thyroid tumors. Tumors on other glands, such as the pituitary, or in the brain itself, are very likely to cause epilepsy.

Exposure

Exposure to a number of toxins, chemicals, medications, and even allergens has been found to cause epilepsy in dogs.

The sudden onset of seizure activity without prior history is a good indicator that your dog has ingested something poisonous. Stimulants, rat poison, pesticides, heavy metals, and toxic plants can all cause seizures. More benign substances, such as xylitol, salt, and alcohol, can also cause abnormal neural activity when ingested by dogs.

Many canine-specific medications are known to have side effects that include seizures. These range from antidepressants to heart medications. 

Especially sensitive dogs may even react to allergens, insect stings, flea bites, and other minor irritants by seizing. Stress and heat are also known to elicit epilepsy in seizure-prone animals.

Trauma

One of the least surprising causes of seizure is an injury to the head. Falls and collisions can all cause damage to the soft tissue of the brain, which can lead to immediate or delayed changes in neurological activity. 

One thing many pet owners don’t realize is that injuries to the neck and spine can cause seizures. Inflammation of the spinal column can cause pressure changes in the brainstem that lead to epilepsy. There is also strong anecdotal evidence that repeated external electrical stimulation in sensitive dogs, such as from invisible fence systems and shock collars, can lead to the development of epilepsy. 

Often, one of the first signs of neck injury in dogs is excessive front paw licking. This symptom doesn’t come from abnormal neurological activity in the brain, but rather nerve damage in the neck. This case is especially common with dogs that pull while on a leash. If left untreated, this minor swelling in the neck could ultimately lead to seizure activity.

If your dog licks their paws frequently, this article can help you determine if the cause is a cervical injury or something else.

Symptoms of Seizures In Dogs

Seizures come in many forms, each with different presentations that can make it hard to know if your dog is truly suffering from seizure activity or something else. 

Grand mal seizures, also known as generalized seizures, are the type most people picture when they think of seizure activity. When a dog has a grand mal seizure, they will typically drop to the ground and their entire body will begin to convulse. These seizures are typically accompanied by full or partial loss of awareness.

Focal, or partial seizures, are less obvious and typically only involve specific parts of the brain. A dog having a focal seizure may be otherwise aware and reactive to the world around them. Eye twitching, obsessive licking, and “fly-biting” are all common presentations of simple focal seizures. These simple seizures can quickly turn into more pronounced episodes as more parts of the brain become affected.

Some of the most common symptoms of seizures in dogs include:

• Falling to the ground
• Limb stiffness or twitching
• Eye twitching
• Repetitive movement
• Sudden loss of consciousness
• Convulsions
• Drooling
• Not reacting to your touch or voice
• Biting or inability to open their mouth
• Uncontrolled urination or defecation

Seizure Phases

Most of the above symptoms present themselves in the “ictal” phase, or active phase, of the seizure. 

All seizures come in three stages, with this middle stage being the most easily identified. How long each of the three phases lasts can vary widely from dog to dog and from seizure to seizure. 

The three stages of a seizure are:

• Pre-Ictal Phase – Also known as the aural phase, this stage encompasses the beginning of seizure activity. Symptoms can be hard to discern in this phase, but often include sudden changes in behavior, such as a desire to hide or a sudden need to be close to people.
• Ictal Phase – During this active phase of the seizure, your dog is likely to show many of the symptoms outlined above. This phase may last only a few seconds to multiple minutes.
• Post-Ictal Phase – In this final phase, your dog’s brain is recovering from the seizure, which may cause confusion, disorientation, balance problems, and restlessness. Your dog may not recognize you during this phase, so it is important to move slowly and keep your hands away from their muzzle.

Seizures can look very scary, but most do not represent an emergent situation. The exceptions are if the ictal phase lasts longer than five minutes or if your dog has more than one seizure in a 24-hour period and has not been previously diagnosed with a seizure disorder. In these cases, it is best to speak to a vet as soon as possible.

If your dog has never had a seizure before and the seizure is short and happens only once, then you should still contact your vet and set up a non-emergent appointment to have them looked at.

Treatment of Seizures In Dogs

Treatment options and approaches for seizures in dogs vary widely based on the circumstances. For instance, most vets will not prescribe medications or treatments for dogs that have had a single seizure. And many will continue this no-treatment approach until repeat seizures become more frequent than once per month.

There is some preliminary evidence that starting treatments earlier (i.e., immediately after recurrent seizure activity has been established) may lead to better long-term seizure control than waiting until numerous seizures have occurred. However, because many seizure medications come with risks, most vets will wait until the effects and frequency of the seizures outweigh the potential risks of the treatment options.

Traditional Methods for Controlling Seizures In Dogs

Humans living with epilepsy have many options for medications to treat the condition. Unfortunately, most of these are not suitable for dogs due to toxicity or ineffectiveness.

While there are many ongoing studies into potential new treatments for controlling seizures in dogs, most vets still only prescribe three options: Levetiracetam, phenobarbital, and potassium bromide.

Levetiracetam

Levetiracetam, or Keppra, is a newer drug in dogs that has proven to be very effective in many cases. Unlike older seizure drugs, this one does not require frequent blood testing for blood concentration levels. It is filtered by the kidneys instead of the liver, which can make it a safer choice for some dogs. 

On the downside, most forms of this drug need to be given three times per day. Dogs are also likely to build up a tolerance over time, meaning you’ll need to give more of the drug to achieve the initial degree of effectiveness. 

Phenobarbital

Phenobarbital is the preferred choice in many situations because it takes effect quickly. This not only allows for faster control of seizures but makes it possible to find the optimal dose for each particular dog more quickly.

However, this drug is also more likely to have side effects. These side effects include increased thirst and appetite, mild sedation, and wobbliness. More extreme side effects are most likely if the blood concentration of the drug goes higher than therapeutic levels. This can result in red and white blood cell count abnormalities and liver damage.

Potassium Bromide

Potassium bromide is much less likely to cause severe side effects compared to phenobarbital. Unfortunately, it takes a much longer time to reach therapeutic levels—about 3 to 6 months. This means it can take a significant amount of time to tailor the dose to be most effective for your dog.

This drug is usually the first choice in dogs with very low seizure activity and those with preexisting liver problems.

Considerations

Whether your dog is put on potassium bromide or phenobarbital, their blood levels need to be checked frequently for two important reasons.

First, with both drug types, a therapeutic blood concentration must be achieved before the drug becomes effective. The dose necessary to achieve this blood concentration varies by individual and can change over time. Blood tests at set intervals can help identify when the right dose has been achieved to maintain the optimal drug blood concentration. Even after this has been determined, occasional blood tests are necessary to assure the dose doesn’t need to be increased with time.

If your dog is on phenobarbital, frequent blood tests are also necessary to check liver function. If the drug concentration level gets too high, it can quickly affect liver levels. In sensitive dogs or those that have been on the medication for a long period, liver damage may occur even if the drug concentration remains within the therapeutic range.

Another thing to understand when putting your dog on traditional epilepsy medication is that about one-third of epileptic dogs do not respond to drug treatments of any kind. In the remaining dogs, effectiveness can vary from completely eradicating seizures to simply reducing their frequency or severity.

Natural Seizure Treatment In Dogs

More recent research into human and dog epilepsy has found two effective natural treatments for seizures: CBD oil and MCT oil.

CBD Oil

Cannabidiol (CBD) oil is a product derived from cannabis. It does not contain the hallucinogenic THC from the plant but does contain a high amount of other cannabidiols known to interact with the central nervous system and the endocannabinoid system.

CBD oil as a treatment for human epilepsy has shown some very promising results. The FDA has recently approved a highly purified oil preparation of CBD. Research studies into this preparation and statistics from real-life use have shown significant improvement in seizure frequency in patients suffering a number of different seizure disorders, including treatment-refractory epilepsy.

While research into CBD oil use in dogs is still in its infancy, preliminary studies are promising. In one small study done at Colorado State University, 90% of epileptic dogs given CBD oil saw a reduction in seizure activity compared to only 20% of those on the placebo.

Additionally, anecdotal evidence gathered during a large-scale veterinary survey found that 77% of vets reported that CBD oil seemed to be “somewhat helpful” or “very helpful” in controlling their patients’ epilepsy.

MCT Oil

Medium-chain triglyceride (MCT) oil is a supplement made from coconut or palm kernel oil that contains a special type of fat. This fat is known to stimulate the production of ketones in the body, a type of energy that has been found to be useful in those suffering from epilepsy.

The brain normally gets its energy from glucose in the blood. Many people and dogs that suffer from seizures are unable to utilize this form of energy correctly, which can lead to cluster and repeat seizures. By increasing ketone levels in the blood, the brain is provided with a different energy source that appears to be less affected by seizure activity, which, in turn, has been shown to reduce seizure activity.

There have been many studies into MCT oil use in epileptic dogs. One small-scale study reported that 47% of treated dogs showed a 50% reduction in seizures, with 27% of those dogs becoming seizure-free by the end of the study. Another study found that 33% of dogs given MCT oil experienced a reduction in seizures over a three-month period.

Like CBC oil, MCT oil appears to be especially effective for treatment-refractory epilepsy and for dogs who never responded well to medication.

A Whole-Picture Approach to Canine Seizures

In the end, whether your dog will require treatment for their seizures depends on the cause and the frequency.

Dogs suffering seizures due to infection, disease, exposure, or trauma will likely see a reduction or cessation in seizure activity as soon as the underlying cause is addressed. For dogs suffering from genetic, structural, or idiopathic epilepsy, treatment options are determined by the frequency and severity of the seizures.

Whether your veterinarian determines that your dog should be treated with medications such as levetiracetam, phenobarbital, or potassium bromides, or not, natural treatments are still worth discussing. CBD oil and MCT oil used in addition to medications or on their own have a great potential for reducing seizure activity in dogs.

Sources

Brauer, C., Jambroszyk, M., & Tipold, A. (2011). Metabolic and toxic causes of canine seizure disorders: A retrospective study of 96 cases. The Veterinary Journal, 187(2), 272–275. 

Dog with Seizures. (2019, December 10). Central Texas Veterinary Specialty & Emergency Hospital. 

Ekenstedt, K. J., & Oberbauer, A. M. (2013). Inherited Epilepsy in Dogs. Topics in Companion Animal Medicine, 28(2), 51–58. 

Erlen, A., Potschka, H., Volk, H. A., Sauter‐Louis, C., & O’Neill, D. G. (2020). Seizures in dogs under primary veterinary care in the United Kingdom: Etiology, diagnostic testing, and clinical management. Journal of Veterinary Internal Medicine, 34(6), 2525–2535. 

L Kogan et al. US Veterinarians’ Knowledge, Experience, and Perception Regarding the Use of Cannabidiol for Canine Medical Conditions. Front Vet Sci, 10 January 2019

Mary Guiden. “Preliminary data from CBD clinical trials ‘promising’.” colostate.edu, 19 July 2018.

Treatment for Epilepsy in Dogs Fact Sheet. (2021, July 8). Davies Veterinary Specialists. 

Types of Seizures. (2021, August 8). Johns Hopkins Medicine. 

Vitale, S., & Foss, K. (2019). Immune-Mediated Central Nervous System Disease—Current Knowledge and Recommendations. Topics in Companion Animal Medicine, 34, 22–29. 

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Sara Seitz worked in the pet industry for over a decade. In addition to being a certified dog trainer, Sara gained experience working as the general manager of a dog daycare and boarding facility, as the creator and manager of a pet sitting company, as a groomer, and as a dog behavior evaluator. She also has a bachelors in animal behavior from CSU. Currently, Sara works as a freelance writer specializing in blog, article and content writing.