Dog Seizures: Signs, Causes, and What To Do When a Dog Has a Seizure

If you’ve never seen a dog having a full-blown convulsive seizure, consider yourself lucky – and hope you never do. It’s awful to watch in any dog. Now imagine he’s yours. 

Seizures come in all shapes and sizes. The big, bad grand mal seizure is a generalized seizure with widespread excessive, aberrant electrical activity occurring in both sides of the brain. Also known as tonic-clonic or convulsive seizure, it’s the one where the dog suddenly falls over with violent, jerking spasms of all four limbs, paddling, frothing at the mouth, losing control of bladder and bowels, with full loss of consciousness. 

WHAT TO DO WHEN A DOG HAS A SEIZURE

First and foremost, make sure you both stay safe. You must stay away from your dog’s mouth to avoid inadvertently being bitten. The natural tendency is to want to comfort your dog by hugging and/or stroking his head. But your dog is not aware during a seizure, nor is he in control of his violent jaw movements. Further, in the minutes to hours after a seizure, called the post-ictal phase, your dog may be disoriented or demented, which can be expressed as aggressive behavior, even rage. You need to be very careful both during the seizure and in the aftermath.

To keep your dog safe, remove any items near him that are breakable or that may fall on him. If he is near a set of stairs, try to stay below him on the stairs so you can prevent him from falling.

Next, time the seizure with your watch. This is important for two reasons. One is for keeping track of your dog’s seizures, in a log or journal, which will be used to determine when the seizures are becoming more severe or more frequent. The second one is because of a life-threatening condition called status epilepticus.

Status epilepticus is an ongoing seizure that doesn’t self-resolve. If a dog is in status epilepticus for too long, he will die, much the way he would die from heat stroke. There is so much intense, violent physical activity going on that the core body temperature rises to life-threatening levels. Status epilepticus requires emergency veterinary intervention with an intravenous medication, usually a benzodiazepine like diazepam (Valium), to break the ongoing seizure.

A good rule of thumb is five minutes. If a dog has been seizing for five minutes, you need to get in the car and get going to the veterinary clinic. If he is still seizing when you get there, he is in dire need of emergency help. If the seizure resolves while you are on your way, you don’t necessarily have to go in and incur an emergency fee. Sit tight for a little bit. If your dog remains quiet, the life-threatening status epilepticus emergency is over.

OTHER TYPES OF DOG SEIZURES

Other generalized seizures include tonic (stiff, extended limbs that don’t move or jerk), clonic (hyperflexed, non-jerking limbs), myoclonic (jerking limbs), and atonic (standing, staring, non-responsive).

Focal seizures, which happen when the abnormal electrical activity is localized to just one spot in the brain, can look like a lot of different things. “Fly-biting” is a classic one, where the dog looks like he is seeing and repeatedly snapping at flies. 

The “chewing gum fit” is where the jaw repeatedly clacks. A focal seizure might just be repeated twitching of an eyelid, lip, or ear. There is not necessarily loss of consciousness. 

These types of seizures rarely present a big problem and usually don’t require treatment. A focal seizure, however, can segue into a generalized seizure, so be sure to keep a close watch until it passes.

CAUSES OF DOG SEIZURES

Seizures can be caused by metabolic disorders like hypoglycemia (low blood sugar), hypocalcemia (low blood calcium), liver disease, liver shunts, kidney disease, and others. These seizures are called reactive seizures. The brain itself is normal, and if the metabolic disorder can be corrected, the seizures go away. 

Some drugs can cause seizures by lowering the seizure threshold in the brain. Discontinuing the drug resolves these reactive seizures.

Toxins, like dark chocolate, caffeine, xylitol (sugar-free sweetener), ethylene glycol (anti-freeze), bromethalin (rat poison), ethanol (liquor), to name a few, can cause seizures. Again, removing and treating for the toxin eliminates the seizures.

Seizures can be caused by abnormalities in the brain itself. These are called structural seizures and are caused by things like tumors, head trauma, inflammatory diseases like granulomatous meningoencephalitis, and infectious diseases like rabies and canine distemper.

Far and away the most common cause of seizures seen in the veterinary clinic is epilepsy. Epilepsy is defined as seizures of unknown origin. There are no structural lesions in the brain. There are no infections, metabolic disorders, drugs, or toxins to blame. A diagnosis of epilepsy is typically made after every other possible cause of seizures has been ruled out.

There are things in addition to a normal physical exam, a normal neurological exam, and normal bloodwork that clue your veterinarian in to the likelihood of epilepsy. The biggest thing is age at onset of seizures. Epilepsy usually starts between 1 and 6 years of age. 

Dogs less than 1 year of age are more likely to have either a congenital defect, an intoxication, or an infectious disease like canine distemper. Dogs who are more than 6 years of age when they have their first seizure are more likely to have a metabolic disorder or a structural brain lesion like a tumor.

Breed predilection toward epilepsy is another clue your vet uses. Schnauzers, Collies, Bassett Hounds, Cocker Spaniels, Labrador Retrievers, and Golden Retrievers are over-represented among dogs with epilepsy.what else can you do

To review: The first time your dog has a seizure, remain calm, stay safe, and time the seizure. Once your dog has recovered, schedule a veterinary exam as soon as possible. 

The first thing your veterinarian has to do is ascertain that the event was indeed a seizure. Capturing it on video is immensely helpful for your veterinarian. The biggest differential for a seizure episode is a cardiac event. If a dog suffers an intermittent cardiac arrhythmia, it can result in confusion, weakness and collapse, which can sometimes be mistaken for seizure activity. Generally speaking, cardiac collapse tends to be softer than seizure activity, more like fainting, and the dog usually recovers much more quickly.

If your veterinarian agrees it was a seizure, she will conduct a physical exam and a thorough neurological exam. Baseline bloodwork should be done to rule out metabolic causes of seizures. Further diagnostics may be recommended from there and could include infectious disease testing, CT scan, or MRI.

TO TREAT OR NOT?

Will your vet recommend that your dog be medicated in an effort to reduce or eliminate his seizures? It depends.

Let’s say your dog is between 1 and 6 years of age, all testing is normal, and a diagnosis of epilepsy is made. Most veterinarians agree starting anti-convulsant drug therapy is generally not indicated after just one seizure. However, the following are exceptions to this rule:

•  Cluster seizures, described as more than three seizures in a 24-hour period, warrant treatment.
• If the seizure was particularly violent, or if it lasted a long time (5 minutes or more) treatment should be considered right away. 
• Certain breeds are notorious for having difficult-to-control seizures. These include the German Shepherd Dog, Border Collie, Irish Setter, Golden Retriever, Siberian Husky, Keeshond, and Saint Bernard. You may not want to wait in these breeds.

For all the others, keep a seizure log where you write down the date and time it happened, now long it lasted, how severe it was, and any other information you think might be pertinent. This log will be used to determine when it might be time to start anti-convulsant therapy.

You might wonder why you wouldn’t just start your dog on anti-convulsants, because you certainly don’t want him to have another seizure. But consider this: Your dog may never have another seizure! Or he may have a mild one once a year. You can’t know until you see how it plays out. And once an anti-convulsant is started, it is generally necessary for life. 

If your dog is one of those epileptics who only has a rare, occasional seizure, you are taxing his body with a medication he really doesn’t need – and you are paying for it! Not to mention that well-managed epileptic dogs on anti-convulsants may still have break-through seizures occasionally. A seizure-free future is not guaranteed, even with long-term medication.

In my opinion, if a dog is seizing as often as twice a month, I think it’s too much for his quality of life, and for yours! I usually recommend starting an anti-convulsant in this case. However, as the person living with and loving the dog, you can and should be the ultimate decider of when enough is enough and it’s time to start.

MEDICATIONS FOR DOG SEIZURES

There are several different anti-convulsants available for dogs. Zonisamide has become the most popular, as it works well with minimal side effects. Phenobarbital, potassium bromide, and levetiracetam (Keppra) are other medications your veterinarian may discuss with you. 

Some dogs may require more than one medication to manage their seizures. Levetiracetam is frequently used as a second medication. It is short-acting, which means it must be dosed three times a day. This can be challenging for dog owners. The extended-release formula, Keppra XR, which is dosed twice a day is much easier. 

A couple of notes on Keppra XR: You cannot split or cut the pills as this destroys the extended-release function. Also, a funny thing about it: You may see the tablet in your dog’s poop, seemingly whole and undigested. Don’t be alarmed. This is okay! The active drug is inside the non-digestible tablet, which has a hole in it. Digestive juices enter through the hole and dissolve the drug, which is then slowly released to be absorbed by the body. This is how the extended-release version works. Once the non-digestible tablet has done its job, it passes safely out with your dog’s feces.

Sometimes, a previously well-managed epileptic starts having more breakthrough seizures. Unfortunately, some dogs will develop tolerance to their anti-convulsant medication over time. In these cases, the liver continuously increases the rate at which it metabolizes the drug, making increasingly higher doses necessary. Higher doses mean more and worse side effects. This can be frustrating and challenging to manage.

TAKE HEART

Seizures in dogs are frightening and difficult for us to observe. Luckily, there are many tools at our disposal to help diagnose and manage this heart-breaking condition.