Preventing seizures in dogs starts with identifying what’s causing them, removing known triggers, and in many cases, managing the condition with daily medication. About 0.6% of dogs have idiopathic epilepsy, the most common chronic neurological disorder in the species, and while it can’t be cured, consistent management can dramatically reduce how often seizures happen and how severe they are.
Find the Underlying Cause First
Before you can prevent seizures, you need to know why they’re happening. Seizures can stem from toxin exposure, metabolic problems like liver disease or low blood sugar, brain tumors, infections, or genetic epilepsy. Your vet will typically start with blood work (a complete blood count and biochemistry panel) and a urinalysis to check for systemic illness. If those come back normal, the next step is usually an MRI to look for structural problems in the brain, such as inflammation or a tumor, and possibly a spinal fluid analysis to check for infection or cancer.
If all tests are normal, your dog will likely receive a diagnosis of idiopathic epilepsy, which essentially means seizures with no identifiable cause. This is a diagnosis of exclusion. Getting the right diagnosis matters because it determines whether prevention means removing a trigger, treating an underlying disease, or starting long-term seizure medication.
Breeds With Higher Seizure Risk
Some breeds carry a significantly higher genetic predisposition to epilepsy. A large study of veterinary hospital admissions across North America found that Border Collies had the highest rate of epilepsy diagnoses at 2.01% of admissions, followed closely by Schipperkes (1.98%), Saint Bernards (1.92%), German Shorthaired Pointers (1.78%), and Keeshonds (1.72%). Irish Setters, Siberian Huskies, Pugs, English Springer Spaniels, and Dalmatians also ranked well above the all-breed average of 0.82%.
If you own one of these breeds, it’s worth knowing the signs of a seizure early. The earlier you start tracking and treating, the better the long-term outcome tends to be.
Remove Household Toxins
A surprising number of common household items can trigger seizures in dogs. Knowing what to keep out of reach is one of the simplest forms of prevention.
- Foods: Dark chocolate, caffeine, xylitol (an artificial sweetener found in sugar-free gum, peanut butter, and baked goods), and excessive salt (including Play-Doh and seawater) can all cause seizures.
- Alcohols: Alcoholic beverages, raw bread dough (which produces ethanol as it ferments), rubbing alcohol, and antifreeze are all dangerous. Antifreeze is particularly deadly and attracts dogs with its sweet taste.
- Pesticides: Rodent poisons containing bromethalin, snail bait with metaldehyde, mole bait with zinc phosphate, strychnine, and common weed killers with organophosphates can all trigger neurological emergencies.
- Heavy metals: Lead from old paint and zinc from swallowed pennies are lesser-known but real risks.
- Household chemicals: Varnishes, shellacs, paints, and windshield washer fluid contain methanol, which is toxic to the nervous system.
If your dog has had a seizure and you suspect toxin exposure, knowing exactly what they ingested helps your vet act fast.
Check Your Flea and Tick Medication
The FDA has issued a specific warning about a widely used class of flea and tick preventatives called isoxazolines. These products have been linked to neurologic side effects including muscle tremors, loss of coordination, and seizures, even in dogs with no prior seizure history. The affected products include some of the most popular brands on the market: Bravecto, Credelio, Nexgard, Nexgard Plus, Simparica, and Simparica Trio.
Most dogs tolerate these medications without problems, but if your dog is epileptic or has ever had a seizure, talk to your vet about alternative flea and tick prevention. There are older product classes that don’t carry this neurological risk.
How Seizure Medications Work
For dogs with idiopathic epilepsy, daily medication is the cornerstone of prevention. The two most established options work by calming electrical activity in the brain.
The first, phenobarbital, is typically the starting medication. It works by enhancing the brain’s main calming signal (a neurotransmitter called GABA), which makes neurons less likely to fire out of control. It’s given twice daily and requires periodic blood tests to make sure levels stay in the therapeutic range and aren’t straining the liver.
The second, potassium bromide, is often added when phenobarbital alone isn’t enough. It works differently: the bromide ion competes with chloride in the brain, raising the threshold at which a seizure can fire. It’s given once daily. Bromide takes longer to build up to effective levels in the body, so your vet may use a higher initial dose for the first five days to speed things along.
Neither medication eliminates seizures entirely in every dog. The goal is usually to reduce seizure frequency by 50% or more while maintaining a good quality of life. Finding the right dose takes time and monitoring, and abruptly stopping either medication can trigger rebound seizures, so consistency is critical.
Dietary Supplements That May Help
Medium-chain triglyceride (MCT) oil has shown real promise as a dietary add-on for epileptic dogs. In a controlled, double-blinded trial published in Frontiers in Veterinary Science, dogs with idiopathic epilepsy received MCT oil alongside their regular diet for three months. Thirty percent of the dogs experienced a 50% or greater reduction in seizure frequency.
The oil appears to work through several pathways at once. MCTs are quickly converted into ketone bodies by the liver, which provide an alternative energy source for the brain. This matters because seizure-prone brains often have energy deficits. The study also found that MCT supplementation significantly increased GABA levels (the brain’s calming neurotransmitter) while shifting the balance away from glutamate, an excitatory signal. Dogs that responded best to the oil also showed lower levels of histamine, glutamate, and serotonin in their urine, suggesting a broader calming effect on brain chemistry.
MCT oil isn’t a replacement for medication, but it may provide additional seizure control for dogs that aren’t fully responding to drugs alone. The study used a dose equivalent to about 9% of the dogs’ daily caloric intake.
CBD Oil
A clinical trial at Colorado State University found that 89% of dogs who received CBD had a reduction in seizure frequency. These results are encouraging, but CBD research in dogs is still in early stages, and dosing, product quality, and drug interactions remain areas of uncertainty. If you’re considering it, bring it up with your vet, particularly because CBD can interact with phenobarbital and affect how the liver processes it.
Reduce Stress and Track Patterns
Stress and anxiety are among the most commonly reported seizure triggers that owners identify. Thunderstorms, fireworks, separation anxiety, visits to the vet, or changes in routine can all lower a dog’s seizure threshold. Predictable daily schedules, regular exercise, and calming strategies during known stressful events can help. For dogs with severe anxiety, behavioral support or anti-anxiety approaches may reduce seizure frequency indirectly.
Keeping a seizure diary is one of the most useful things you can do for long-term prevention. Each time your dog has a seizure, record the date, time of day, how long it lasted, what medications they’re on (including doses), and what the seizure looked like, including any unusual behavior afterward like disorientation or restlessness. Over weeks and months, patterns often emerge: seizures clustering around stressful events, particular times of day, or dietary changes. This log becomes invaluable for your vet when adjusting medications or investigating new triggers.
Consistency Is the Core Strategy
The most effective seizure prevention in dogs comes down to consistency across every dimension: giving medication at the same times each day, feeding a stable diet, minimizing exposure to known toxins and stressors, and keeping up with regular blood work to ensure medication levels stay where they need to be. Missed doses, sudden diet changes, and skipped vet appointments are among the most common reasons seizure control slips. Dogs with well-managed epilepsy often live full, normal lifespans, but that management requires daily commitment from their owners.