Dog seizures happen without warning and last anywhere from seconds to several minutes. For an owner watching their dog convulse for the first time, it is one of the most frightening experiences in pet ownership — and the instinct to hold the dog or put something in its mouth (both wrong) can make things worse. This guide gives you the exact emergency protocol, explains what seizures actually are, covers the most common causes, and tells you precisely when you are dealing with a life-threatening emergency versus a manageable chronic condition.
During a dog seizure: stay calm, clear the area of hard objects, do not restrain the dog, do not put your hands near its mouth, time the seizure, and keep the environment dark and quiet. Call an emergency vet immediately if the seizure lasts more than 5 minutes, if the dog has more than two seizures in 24 hours, or if the dog does not recover consciousness between seizures. These are status epilepticus — a life-threatening emergency.
What Happens During a Dog Seizure — What You Are Actually Seeing
A seizure is an uncontrolled burst of electrical activity in the brain. The muscles receive conflicting signals simultaneously, causing involuntary movement. It is not painful — the dog is unconscious and unaware during the convulsive phase.
The Three Phases of a Seizure
Phase 1 — Pre-ictal (Aura): minutes to hours before the seizure, some dogs show behavioural changes — restlessness, clinginess, staring into space, anxiety, salivating. Not all dogs show a pre-ictal phase.
Phase 2 — Ictal (The Seizure Itself): the active convulsive phase. Duration: typically 30 seconds to 2 minutes. Longer than 5 minutes = emergency (status epilepticus).
Phase 3 — Post-ictal (Recovery): after the seizure ends, the dog may be confused, disoriented, temporarily blind, very thirsty, or excessively tired. This phase lasts minutes to hours and is entirely normal. Do not confuse the post-ictal phase with a new seizure.
| Seizure Type | What It Looks Like | Notes |
|---|---|---|
| Grand mal (generalised tonic-clonic) | Full body convulsions, paddling legs, loss of consciousness, jaw chomping, urination/defecation | Most common type; most frightening to witness |
| Focal (partial) seizure | Repetitive movement in one body part — facial twitching, one leg paddling, rhythmic blinking | Dog may remain conscious; can progress to grand mal |
| Atonic seizure | Sudden muscle collapse — dog drops to the floor without convulsing | Can look like fainting; differentiated by post-ictal phase |
| Absence seizure | Brief staring episodes, unresponsive for seconds | Less common in dogs than humans; easily missed |
The Emergency Protocol — What to Do Step by Step
- Step 1: Stay calm and look at the clock immediately — start timing the seizure
- Step 2: Remove hazards — push furniture away, place a cushion under the dog’s head if safe to do so without touching the face
- Step 3: Do NOT restrain the dog — you cannot stop a seizure by holding the dog; restraint causes injury and distress
- Step 4: Do NOT put your hands near the dog’s mouth — dogs cannot swallow their tongues (this is a myth); a seizing dog bites reflexively and hard
- Step 5: Turn off lights and reduce noise — lower visual and auditory stimulation shortens recovery
- Step 6: Keep other pets and children away from the dog during and immediately after the seizure
- Step 7: Once the seizure stops, speak calmly and softly — the dog is disoriented and needs reassurance
- Step 8: Call your vet even if the dog seems recovered — a first seizure always warrants immediate veterinary assessment
When to Go to an Emergency Vet Immediately
- The seizure lasts more than 5 minutes (status epilepticus — brain damage risk increases rapidly)
- The dog has more than 2 seizures within 24 hours (cluster seizures)
- The dog does not regain consciousness between seizures
- The dog was hit by a car, fell from height, or suffered head trauma before the seizure
- The dog is a puppy under 6 months (seizures in puppies are almost always pathological)
- You know or suspect the dog ingested a toxin, medication, or plant
What Causes Dog Seizures — The 12 Main Causes
| Cause | Age of Onset Typical | Notes |
|---|---|---|
| Idiopathic epilepsy | 1–5 years | Most common cause in young adult dogs; genetic; no underlying disease found |
| Brain tumour | 5+ years | New-onset seizures in middle-aged or older dogs require brain imaging |
| Head trauma | Any age | After injury; emergency evaluation |
| Toxin ingestion | Any age | Xylitol, rat poison, certain plants, slug pellets, some human medications |
| Hypoglycaemia (low blood sugar) | Any age | Common in very small breeds, diabetic dogs on insulin, newborn puppies |
| Liver disease (hepatic encephalopathy) | Any age | Toxins build up in the bloodstream when the liver cannot filter them |
| Kidney failure | Middle-aged+ | Uraemic toxins cross the blood-brain barrier |
| Hypothyroidism | Middle-aged+ | Rare but possible; thyroid hormone affects neurological function |
| Electrolyte imbalances | Any age | Severe sodium, potassium, or calcium abnormalities |
| Infectious disease (distemper, encephalitis) | Any age | Distemper: more common in unvaccinated dogs |
| Heatstroke | Any age | Seizures occur in severe, prolonged heatstroke |
| Heart disease | Any age | Cardiac arrhythmias can cause syncopal episodes that mimic seizures |
Idiopathic Epilepsy — The Most Common Cause in Young Dogs
If your dog is between 1 and 5 years old, has no other symptoms, and the vet cannot find an underlying cause after workup, idiopathic (primary) epilepsy is the most likely diagnosis. It is a structural neurological condition with a genetic component — certain breeds are significantly predisposed:
High-risk breeds: Belgian Malinois, Labrador Retriever, Border Collie, Australian Shepherd, German Shepherd, Boxer, Beagle, Dachshund, Irish Setter, Bernese Mountain Dog.
See our Labrador Retriever Guide for breed-specific health screening recommendations that include neurological considerations.
Idiopathic epilepsy is manageable with daily anticonvulsant medication. It is not curable, but most dogs with controlled epilepsy live full, normal lives.
Diagnosing the Cause — What the Vet Will Do
A first seizure in an adult dog with no obvious trigger typically prompts:
- Full physical and neurological examination
- Blood chemistry panel (liver, kidney, glucose, electrolytes)
- Thyroid function test
- Urine analysis
- Blood pressure measurement
- If bloodwork is normal and the dog is over 5 years old: MRI of the brain and cerebrospinal fluid (CSF) analysis to rule out structural brain disease
- If the dog is 1–5 years old with normal bloodwork: provisional diagnosis of idiopathic epilepsy
Anticonvulsant Medications — What Vets Actually Prescribe
| Medication | Form | Notes |
|---|---|---|
| Phenobarbital | Oral tablet, twice daily | First-line treatment for most dogs; highly effective; requires liver enzyme monitoring every 6 months |
| Potassium bromide (KBr) | Oral solution or tablet | Often combined with phenobarbital for seizures not controlled by one drug alone; requires 3–6 months to reach therapeutic levels |
| Levetiracetam (Keppra) | Oral tablet, three times daily | Good add-on drug; fewer side effects than phenobarbital; expensive as primary drug |
| Zonisamide | Oral capsule, twice daily | Alternative to phenobarbital with fewer liver side effects; used in refractory cases |
| Diazepam (Valium) rectal | Emergency rescue gel | Given at home for cluster seizures to stop status epilepticus before reaching the vet |
Home rescue medication — when to use it
If your vet has prescribed rectal diazepam gel (or nasal midazolam) for home emergency use, use it if:
- A seizure lasts more than 3–4 minutes without signs of stopping
- More than one seizure occurs within 6 hours
- The dog appears to not fully recover between seizures
Administer as directed by your vet and go to the emergency vet immediately after administration regardless of whether the seizure stops.
Living with an Epileptic Dog — Practical Management
- Keep a seizure diary: record date, time, duration, pre-ictal signs, recovery time, and any possible triggers (stress, heat, missed medication). This is invaluable for your vet to adjust treatment
- Never miss a medication dose — missing phenobarbital can trigger breakthrough seizures or status epilepticus
- Avoid known triggers: some epileptic dogs are sensitive to flashing lights, extreme stress, or specific foods. Track patterns in the diary
- Swimming: epileptic dogs should not swim unsupervised — a seizure in water is rapidly fatal
- Inform dog walkers, boarders, and anyone caring for your dog — provide written emergency instructions and the emergency vet number
- ID tags: consider adding “Epileptic Dog — Has Medication” to the dog’s tag
Frequently Asked Questions
Is my dog in pain during a seizure?
No. Dogs are unconscious during a generalised seizure and are not experiencing pain or fear in the moment. The post-ictal period (confusion, temporary blindness, exhaustion) can be distressing for the dog, but the seizure itself is not painful. The distress you observe is your own — understandably — not the dog’s during the active episode.
Can a dog die from a seizure?
A single short seizure is not life-threatening. Status epilepticus — a seizure lasting more than 5 minutes, or multiple seizures without recovery — is life-threatening. Sustained seizure activity causes brain temperature to rise, neurons to die, and eventually cardiac failure. This is why the 5-minute threshold is the critical emergency line.
My dog had one seizure and the vet found nothing wrong — why won’t they prescribe medication?
Most veterinary neurologists recommend not medicating after a single isolated seizure in a young dog with a normal workup. The rationale: anticonvulsant medications have real long-term side effects (liver strain from phenobarbital), and a single seizure may never recur. Medication is typically started after the second seizure, or immediately if the first seizure was severe (cluster or prolonged).
Can stress trigger dog seizures?
Stress can lower the seizure threshold in epileptic dogs — meaning a dog that is otherwise stable on medication may have a breakthrough seizure during a period of high stress (boarding, fireworks, illness). This is why managing overall anxiety and avoiding known stressors is part of epilepsy management. Stress alone does not cause idiopathic epilepsy in a dog that did not already have it.
Sources
- American College of Veterinary Internal Medicine — Epilepsy Guidelines
- Merck Veterinary Manual — Seizure Disorders in Dogs
- Cornell University College of Veterinary Medicine — Canine Epilepsy
- International Veterinary Epilepsy Task Force — Consensus Statements