What Toxins Can Cause Seizures in Dogs?

One of the scariest medical emergencies for any loving pet parent is to see their beloved furry friend having a seizure. You feel helpless and frightened for your dog, and of course, you wonder what might have caused it.

Though most dog seizures are over within a few seconds, they leave an indelible mark on your psyche as you fear there will be more. That’s why it’s important for pet owners to understand dog seizures, what can cause them, and what you should do if you witness one.

What Kinds of Dog Seizures Are There?

A seizure is a strong burst of electrical activity in the brain that can cause convulsions and loss of consciousness. Some seizures, like petit mal seizures, may go unnoticed, but larger seizures, called gran mals, may cause strong convulsions, urination, defecation, and disorientation.

While you typically think of seizures as causing a loss of consciousness, there is something known as a focal seizure in which your dog may remain conscious. Usually, this type of seizure involves abnormal movements of just a single body part, like an ear or one of the legs. Moreover, lingering side effects can include a temporary change in temperament in your dog following a seizure.

Seizure activity can vary from animal to animal and from one seizure to another, and if your dog is experiencing this medical problem, you’ll want to understand the underlying causes and treatment options.

What are the Causes of Seizures in Dogs?

There are several things that can cause a seizure in your dog, and these are the basis for how they are classified. Here are a couple of different types of seizures:

• Idiopathic epilepsy: This is the type of seizure that has no identifiable cause. It is likely due to underlying genetic influences, and this is the most common type of seizure. It is seen more commonly in certain breeds of dogs, including:
  • Beagles, Bernese Mountain Dogs,
  • Border Collies, Boxer Dogs,
  • Cocker Spaniels,
  • Collies,
  • Dachshunds,
  • Golden Retrievers,
  • Irish Setters,
  • Irish Wolfhounds,
  • Keeshonds,
  • Labrador Retrievers,
  • Poodles,
  • St. Bernards,
  • German Shepherds,
  • Shetland Sheepdogs,
  • Siberian Huskies,
  • English Springer Spaniels,
  • Pembroke Welsh Corgis,
  • Wire-Haired Fox Terriers.
• Symptomatic Seizures: This is the type of seizure that is due to some kind of structural change within the brain. This might be from inflammation, infection, brain tumors, strokes, or even a malformation that has been present since birth. Sometimes, the brain itself is not infected, but an infection is present in the cerebrospinal fluid that cushions the brain. Additionally, certain diseases can cause seizures, like kidney disease or liver disease.
• Reactive Seizures: These are the types of seizures that result from some kind of metabolic disorder or from exposure to toxins that affect the brain. Metabolic disorders include problems like low blood sugar and calcium or other electrolyte imbalances that may result from dehydration or other medical conditions. Toxicity, for its part, accounts for some 200,000 cases of pet poisoning every year in the United States, according to the ASPCA. There are a number of toxins that can cause dog seizures, including things like inhaling smoke and the ingestion of killer bees!

What Kinds of Toxins Cause Dog Seizures?

There are different kinds of toxins that can cause a seizure in your dog. Let’s take a look at the different categories of toxins that are a common cause of seizures.

1. Alcohols

There are several types of alcohol that, if ingested, can cause seizures in your dog. Here is a list of some of the more common types of alcohol that are present in many household items.

• Ethanol, which is found in alcoholic beverages and raw bread dough
• Isopropanol, which is another name for rubbing alcohol
• Methanol, which is found in paints, windshield wiper fluids, adhesives, and varnishes and shellacs
• Ethylene Glycol, which is the active ingredient in antifreeze and is very tasty to both pets and children

2. Animal Compounds

There are also some compounds produced by animals that can cause dog seizures. Your dog can come into contact with these if he likes to investigate other animals.

• Bufo Toad — Bufo toads are native to Central and South America, but they were introduced to Florida in an attempt to control other pests. They are now found in parts of Texas, Hawaii, and Central and South Florida. These are also known as the cane toad and the marine toad. When they feel threatened, they release a creamy-looking poison.
• Killer Bees — When you think of killer bees, you think of Africanized killer bees, but the reality is that African killer bees have the same kind of toxin as any regular honeybee. They are simply more aggressive and tend to attack in swarms. Whether Africanized or not, an attack by a swarm of honeybees can cause seizures in your dog.

3. Carbon Monoxide

The culprit in carbon monoxide poisoning is hypoxia, and it actually creates lesions in a dog’s brain. What happens is that when carbon monoxide is inhaled, it combines with the hemoglobin in the blood. Hemoglobin is what carries oxygen to the cells of the body, and when the carbon monoxide combines with hemoglobin, it reduces the oxygen delivery to the body.

Your pooch can be exposed to toxic levels of carbon monoxide in as little as ten minutes. Common sources of this lethal, colorless, odorless gas include kerosene or propane heaters, gasoline engines, automobile exhaust, and fumes from carbon-based fuel heating systems.

4. Human Foods

Human food may be safe for us, but that doesn’t mean they’re safe for your dog. Some common foods that can cause toxicity in dogs are the following:

• Caffeine and dark chocolate — These contain methylxanthines, which are toxic to dogs and, in severe cases, can cause seizures.
• Salt — Excessive salt is toxic to your pup, and they may come into contact with it in your household through table salt or rPlay-Dough ingestion. While commercial Play-Doh™ doesn’t usually contain enough salt to cause lethal toxicity, it can cause gastrointestinal upset in your pooch. Homemade Play-Dough, however, often contains excessive amounts of salt that can cause toxicity.
• Xylitol — This is an artificial sweetener that is found in many products and is highly toxic to dogs. It’s also known as birch sugar or wood sugar, and it is found in many sugar-free gums, mints, and some chocolate bars. Here’s a list of some of the common sources:
  • breath mints
  • baked goods
  • cough syrup
  • children’s and adult chewable vitamins
  • mouthwash
  • toothpaste
  • some peanut and nut butters
  • over-the-counter medicines
  • dietary supplements
  • sugar-free desserts, including “skinny” ice cream

5. Heavy Metals

There are some metals that are toxic to you and your pooch. Just as with humans, dogs may be exposed to lead through paints that contain lead. They can be exposed to zinc by ingesting pennies.

It’s common for your furry friend to explore his world by sniffing, licking, and even eating items around the house, and some of these may contain toxic levels of metal, which can cause seizures in dogs.

6. Illicit Drugs

Dogs are always curious about anything around the house. They frequently investigate anything within their reach by sniffing, tasting, and eating what they find. If they encounter illicit drugs, they can easily ingest them, and seizures can result. Here are some drugs that can cause seizures in your furry friend.

• Amphetamines
• Methamphetamines
• Cocaine
• Marijuana
• Opiates

7. Medications

Illicit drugs are not the only kind of drug that can cause problems for your pooch. Human medications can often cause problems in pets. Here are some that can cause seizures.

• Analgesics like aspirin and Ibuprofen are common household pain relievers that work well in humans but can be toxic to your pets.
• Antidepressants, including SSRIs (Selective serotonin reuptake inhibitors) and TCAs (tricyclic antidepressants), can cause seizures in pets and should be kept out of reach of your furry buddies.
• Theophylline is a medication for asthma, and it is another human medication that causes seizures in pets.
• Chlorpheniramine is a common antihistamine that may relieve your itchy eyes but can cause seizures in your dog.
• 5-Fluorouacil is a cancer medication that comes as an injection and a cream. The cream, which many people may have around the house, is used to treat actinic keratosis, a skin condition that can become cancerous. It should be kept out of reach of your dog, however, because it can cause seizures.
• Beta-blockers are common cardiac medications that many people need to prevent problems. if your dog gets it, however, it could cause seizures.
• Decongestants like Ephedrine and Pseudoephedrine can also cause seizures in your pets.
• Muscle Relaxants, including Baclofen, Carisoprodol, Methocarbamol, Tizanidine, and Cyclobenzaprine, can all cause seizures in dogs.

8. Pesticides and Insecticides

There are a number of everyday pesticide and insecticide toxins that are capable of causing seizures in dogs. These include the following:

• Strychnine
• Bromethalin (rodenticide)
• Organophosphates and Carbamates (weed killers)
• Pyrethrins and pyrethroids
• Metaldehyde (snail bait)
• Zinc Phosphate (mole bait)

9. Plants

Plants are another possible source of toxins that can cause seizures in dogs. It’s something you might not think about when choosing a plant to decorate your house or to spruce up your holiday. Here are some to keep in a place that’s out of reach of your dog:

• Brunfelsia is a member of the nightshade family and is very toxic to humans and animals if ingested. It can cause seizures in your dog.
• Mushrooms, like panther cap, fly agaric, gemmed amanita, Smith’s amanita, and warted amanita, are toxic to dogs.
• Humulus Lupulus, also known as the common hop or hops, is a flowering plant in the hemp family Cannabaceae native to West Asia, Europe, and North America.
• Sago Palm is native to West Asia, Europe, and North America, and it can cause seizures in dogs.

What are the Clinical Signs of a Seizure in Dogs?

You might not notice it, but there are subtle signs that your dog is having a seizure that actually start before convulsions are evident. He might seem anxious, clingy, or unsteady on his feet. After a seizure, he might also become disoriented, try to hide, or even become temporarily blind. What most people notice, however, are the more obvious signs of a seizure. These include the following:

• Collapsing
• Muscle twitching
• Stiffening
• Paddling motions with their legs
• Jerking body movements
• Drooling
• Chomping or tongue-chewing
• Foaming at the mouth
• Loss of consciousness
• Involuntary defecating or urinating

What Should You Do If Your Dog Has a Seizure?

As frightening as a seizure is, it is not usually painful. Though you might want to touch or hold your dog during a seizure, it’s best to avoid doing so. You won’t be able to help him, and you might possibly be bitten accidentally.

The first thing to do if your dog is having a seizure is to stay calm. There are some things you can do to help keep your pooch from hurting himself. This includes removing anything from the immediate area that your dog might run into and get hurt. You’ll also want to ensure he can’t accidentally fall off of furniture or down the stairs.

Another thing to do is to time the seizure so you can give that information to your DVM, and it can also help to record it if you can. Of course, you’ll want to call your veterinarian and get your dog to see them as soon as possible. It’s important to find out what might have caused it so that you can initiate appropriate treatment.

Whatever you do, DO NOT try to insert anything into your dog’s mouth during a seizure. If you do, he may bite the object you insert, and it can become a choking hazard. You might also get bitten if you try to do that. If your dog vomits during the seizure, however, you’ll want to collect a sample of that and any potential toxin he may have ingested.

When to Go to the Vet

If your dog has more than two seizures in a 24-hour period or a seizure that lasts more than three minutes, you should NOT wait for the seizure to end to get him to the vet. Seizures that last more than five minutes in length or if your dog has more than one seizure within a five-minute period of time without returning to normal consciousness is a condition called status epilepticus. This is a medical emergency that can result in permanent brain damage or death if you don’t get your dog to a veterinarian immediately.

Call the Animal Poison Control Center for Suspected Toxins

Another thing to remember is that there is an animal poison control center that can help you determine if your dog has been exposed to something toxic. The ASPCA 24/7 Poison Control Hotline is 888-426-4435 or the Pet Poison Helpline is 855-764-7661. These are handy numbers to have on hand in the event of an emergency. They can help you triage your dog as you work to get him to the vet.

This content is for informational use only and does not replace professional nutrition and/or medical advice, diagnosis, or treatment. It is not a substitute for and should not be relied upon for specific nutrition and/or medical recommendations. Please talk with your veterinarian about any questions or concerns.

Citations

Kent, Marc, Kate E. Creevy, and Alexander deLahunta. 2010. “Clinical and Neuropathological Findings of Acute Carbon Monoxide Toxicity in Chihuahuas Following Smoke Inhalation.” Journal of the American Animal Hospital Association 46 (4): 259–64. https://doi.org/10.5326/0460259.

Mughal, Mudassar, Ghazanfar Abbas, Muhammad Saqib, and Ghulam Muhammad. 2014. “Massive Attack by Honeybees in a German Shepherd Dog: Description of a Fatal Case and Review of the Literature.” Journal of Venomous Animals and Toxins Including Tropical Diseases 20 (1): 55. https://doi.org/10.1186/1678-9199-20-55.