What Causes Dog Seizures and Tremors? | The Difference Between Seizures and Tremors in Dogs

By David F. Kramer

Perhaps one of the most disturbing things a dog owner can experience is a bout of uncontrollable shaking in their pet. Involuntary movements can be caused by tremors or seizures, but the two conditions differ with respect to their origin, diagnosis, and treatment. Knowing what makes tremors and seizures alike and different will help you get the help your dog needs. 

What Are Tremors and Seizures?

Dr. Sarah Moore, Associate Professor of Neurology and Neurosurgery at the Ohio State University Veterinary Medical Center, describes the difference between tremors and seizures:

“Tremors are an involuntary muscle movement. During an episode of tremors the dog is awake and aware of its surroundings, which can help distinguish tremors from seizures (where the dog usually has decreased consciousness).”

A seizure, on the other hand, is evidence of a sudden abnormal and uncontrolled surge of electrical activity in the brain, which often results in altered consciousness. Where the activity occurs in the brain determines the signs that are seen. A seizure is not a disease in and of itself, but a symptom of something else that is going on in the body or brain.

Are Some Dogs More Likely to Have Tremors and Seizures?

“Some of the early signs of neurologic dysfunction can be vague, such as decreased activity levels or changes in personality. Other things to look for would include difficulty using one or more limbs, loss of balance, trouble jumping on or off furniture, or difficulty climbing stairs,” says Moore. But in some cases seizures or tremors seem to strike out of the blue.

Sometimes, the breed of your dog can make it a candidate for specific types of neurological disorders.

“We definitely see a predisposition for particular problems in certain breeds. For example, there is an autoimmune problem of the cerebellum that is more common in young adult toy-breed dogs. And some diseases that cause tremors due to weakness are more common in large breed dogs,” says Moore.

Dr. Adam Denish of Rhawhurst Animal Hospital in Pennsylvania says he has “seen hundreds, if not thousands, of dogs with seizures.”

“I do see a hereditary pattern in some animals, but we often don’t have information on the parents or littermates. In-breeding and poor breeding choices can lead to these repetitive disease conditions being passed on unnecessarily,” says Denish.

What Causes Seizures and Tremors?

Moore says that “tremors can be caused by a variety of problems, such as behavioral causes (fear, anxiety), electrolyte imbalances, problems of the nerve or muscle, weakness/fatigue, exposure to certain toxins, and problems in certain areas of the brain such as the cerebellum.”

Dogs can suffer from seizures after serious traumas, such as being struck by a car, or other accidents that might result in brain injury. “Another common cause of seizures in dogs is idiopathic epilepsy, a condition that seems to have a strong genetic component but for which no other underlying cause of the seizures can be found,” says Dr. Jennifer Coates, a veterinarian in Fort Collins, CO. “Other possible causes of seizures include brain infections, brain tumors, inflammatory disorders, stroke-like events, low blood sugar, liver failure or other metabolic conditions, hormonal disorders, electrolyte imbalances, and the ingestion of toxins.” 

Types and Phases of Seizures

There are many different ways to classify the different types of seizures that dogs can have. Coates uses this system:

• Focal Seizures (sometimes called partial seizures) – in these cases, only a particular area (or several particular areas) of the brain are being affected by the seizures. Dogs will typically exhibit specific movements like lip licking or fly biting (snapping at the air). Dogs may or may not experience altered consciousness with focal seizures
• Generalized seizures – in these cases, most if not all of the brain is involved in the seizure. The most common type of generalized seizure we see in dogs is the tonic-clonic (also called grand-mal) seizure where dogs fall over, become stiff, paddle their limbs, and may urinate or defecate. Other types of generalized seizures are also possible, but in all of them the dog appears unaware of its surroundings.

Seizures also have specific phases. “Some animals will have what we call a pre-ictal phase. That is, some behavioral or medical sign that shows that a seizure is impending. Animals will also have a post-ictal phase, which is the period after the seizure when their body is coming out of it but they still seem to be ‘off,’” says Denish.

Some of the pre-ictal symptoms to watch for include sudden, unwarranted fearfulness; sniffing, maybe in response to the phantom smells that some people report prior to a seizure; licking the lips; and pawing at the head, perhaps in response to a headache.

What to Do if Your Dog Has a Seizure 

Perhaps the most difficult part of dealing with your dog’s seizure is keeping yourself calm. Seizures are disturbing and heartbreaking to witness, but keeping a clear head will help you deal with the situation. It’s best to keep your distance and not try to hold the dog down or put anything in its mouth because they can easily bite without meaning to.

While people often hear that it’s necessary to keep a seizure victim from swallowing their tongue, there’s no need to worry about this in dogs. Again, it’s best to just let the seizure take its course, but be aware of the dog’s surroundings and remove any objects or hazards that could potentially injure your dog.

Once your dog recovers from a seizure, you can use pillows or a blanket to cradle his head. Keep other pets clear and give the dog a chance to rest and recuperate. Your dog may feel confused, sleepy, or unresponsive, and may remain fearful. Once your dog is aware again and able to walk and drink, offer him some water and give him an opportunity to urinate or defecate in his usual spot.

Seizures in dogs are often an ongoing issue, so keep a log of when they occur, how long they last, and any unique information associated with them. This information can be of great help to your vet, and can also help you to recognize factors and situations that might trigger your dog into a seizure and give you a chance to avoid or remove the triggers.

Seizures that are especially severe, last for more than a few minutes, or occur in clusters are especially dangerous and warrant an immediate trip to the nearest veterinarian.

Treatment for Seizures and Tremors

If your dog suffers from tremors or seizures, your vet might employ a battery of medical tests to find the cause, including MRIs and CAT scans, blood work, urinalysis, or X-Rays. Your vet may take a sample of your dog’s spinal fluid to check for abnormalities. Once your dog receives a diagnosis, your vet will devise a course of treatment that could include therapies aimed at specific underlying causes and/or medications to control the tremors or seizures, assuming they are severe enough to warrant treatment. 

“With animals, we do use the same medications that are useful in human subjects. Obviously, there are some cost issues with using the newer human medications. We generally start with the older, simpler medications like phenobarbital or diazepam (Valium), however we also use medications like Keppra and potassium bromide, as well as gabapentin and zonisamide,” says Denish.

While there are vets who specialize in neurological issues, you might not necessarily need to enlist the help of a specialist.

“Most cases of seizures or tremors can be handled by a conventional vet,” says Denish. “However, even we will seek the help and guidance of a veterinary neurologist in difficult cases, or cases that don’t respond appropriately to medicine. Additionally, stress and other secondary diseases like Diabetes, Cushing’s Syndrome, and Hypothyroidism can all play a role in making seizures worse in the patient.”

Seizure and Tremor Management

If your dog is affected by tremors, some life changes may need to be made, but this depends on their severity. It may be best to avoid excessive excitement or stress in your dog, and sometimes even vigorous play should be avoided. If your dog is going to exercise, it’s best to keep it as low key and sedate as possible, like a walk around the neighborhood. Your vet can offer you guidelines based on your dog’s specific condition..

Recommendations for seizures are a little different. “Luckily, most dogs are normal between seizure episodes. That’s good news for the pet but it can make it difficult to see when a seizure actually occurs. Owners could be at work while the dog has a seizure and come home to find a normal and happy-go-lucky dog,” says Denish. Coates adds that depending on the cause of the seizures or what it is that seems to trigger them, lifestyle modifications may be in order.

With proper veterinary care, a dog’s prognosis is often good.

“Many of the potential causes of tremors [and seizures] can be managed effectively so that pets can live a normal lifespan and have a good quality of life,” says Moore.