The Canine Ledger

First Seizure: What to Do, and What Counts as an Emergency

What to do during a dog's seizure, the five-minute line, when one seizure becomes an emergency, and why a first seizure is a reason to see a vet.

Written by thecanineledger

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If your dog is having a seizure right now: keep your hands away from the mouth. Move anything that could hurt them, and get them away from stairs or off furniture if you can do it safely. Start a timer. If it lasts more than two minutes, phone your vet or an emergency clinic and follow their advice. If it passes five minutes, or a second seizure starts before your dog has come round, this is an emergency. Don’t put anything in your dog’s mouth, not even food or sugar.

In a study of 96 dogs whose seizures were caused by something outside the brain, the two most common causes were poisoning, in 39%, and low blood sugar, in 32% (De Risio et al., BMC Veterinary Research 2015, citing an earlier study). In the same study, 41% arrived in a seizure that would not stop.

That is why a first seizure matters, even one that is over in a minute. Most dogs who have one seizure do not have a poison or a blood sugar problem. But the vet has to rule those out, and some of them need treating quickly.

While a seizure is frightening to watch, most stop on their own, and there is little an owner needs to do during one. This page covers that little, the line where a seizure becomes an emergency, and what usually happens next.

1. During the seizure

The classic seizure is easy to recognise. Cornell University’s Riney Canine Health Center describes a dog who “suddenly falls over with violent, jerking spasms affecting all four limbs, paddling, frothing at the mouth, possible loss of bladder and bowel control, and loss of consciousness” (Cornell, Managing seizures).

Cornell and PDSA, a UK veterinary charity, give owners the same core steps (PDSA, What to do if your pet has a seizure, published February 2023):

  • Keep away from the mouth. PDSA: “Don’t get anywhere near their mouth – you are likely to get bitten.” Your dog is not aware of you, and is not choosing to bite.
  • Make the space safe. Cornell: “remove any items near them that are breakable or that may fall on them.” PDSA suggests moving a dog on a sofa or bed carefully onto the floor.
  • Don’t hold your dog down. PDSA: “Don’t restrain them – you might end up hurting them or yourself.”
  • Don’t try to wake them. PDSA warns against “shouting, shaking or hitting them”, which “will probably make their seizure worse.”
  • Keep it cool, dim and quiet. PDSA: “seizures often cause a rise in body temperature”, so don’t wrap your dog in a blanket.
  • Time it, and film it if you can. Cornell: “Your veterinarian must determine if the event was indeed a seizure, so a video can be immensely helpful.”

Put nothing in the mouth. The 2026 RECOVER first-aid guidelines, from an international veterinary emergency initiative, are direct: “In dogs and cats with active seizures, we recommend against oral or mucosal administration of any substance in the prehospital setting” (Mandell et al., Journal of Veterinary Emergency and Critical Care 2026). That includes honey or sugar, even in a dog you think has low blood sugar.

2. When a seizure becomes an emergency

The 2024 consensus statement from the American College of Veterinary Internal Medicine (ACVIM) sets out the line: “Seizures are considered an emergency when their duration is prolonged and they are not self‐limiting, or when they occur as a closely grouped series” (Charalambous et al., Journal of Veterinary Internal Medicine 2024).

In practice, that means two things.

A seizure that lasts more than five minutes. This is status epilepticus. The consensus describes it as “any prolonged seizure lasting >5 minutes”, following the international definition. A veterinary task force also counts two or more seizures “without recovery of consciousness in between”.

Seizures that keep coming. The consensus describes cluster seizures as “>2 self‐limiting seizures over a period of 24 hours.”

Why five minutes matters. Cornell’s Dr Peter Early explains that “Status epilepticus is an ongoing seizure that doesn’t self-resolve, typically considered more than five minutes.” The consensus explains why vets treat it so seriously: once a seizure has lasted more than five minutes, it “is most likely to be prolonged and potentially non‐self‐limiting.” In animals, it gives the mortality rate of status epilepticus as “25.3%‐38.5%”.

Why we say phone at two minutes. PDSA tells owners to call the vet “if the seizure lasts for more than two minutes, or if it isn’t the first one your pet has had in the past 24 hours.” That is earlier than the five-minute definition, and we think it is the right instruction for owners. A phone call at two minutes means the clinic knows you are coming if the seizure reaches five. PDSA also advises: “Don’t transport your pet until the seizure has stopped (unless your vet advises otherwise).”

Our note: We combine PDSA’s two-minute “phone” line with the consensus’s five-minute “emergency” line.

Time it with a clock, not a feeling. Seizures feel far longer than they are. There is also a trap in the other direction. Merck notes that “Owners sometimes mistakenly consider the postictal period as part of the seizure when describing its duration” (Merck, Epilepsy in Small Animals). The postictal period is the recovery afterwards. The seizure itself is the convulsing; the confused wandering after it is not.

→ Emergency Signs in Dogs: When to Go Now, Not Tomorrow

3. Afterwards

Expect confusion. Cornell warns that in “the minutes to hours after a seizure”, a dog “may remain disoriented or confused, which can sometimes be expressed as aggressive behavior. You need to be careful.” Give your dog space, and keep children and other pets away until they are themselves again.

Phone your vet, even if your dog seems fine. PDSA lists this as a reason to call, “even if they seem perfectly fine afterwards.” For a first seizure, this call matters most.

Our note: If a first seizure was short, has stopped and your dog is recovering, phone your vet. If you can’t reach them, treat it as an emergency.

4. Why a first seizure needs a vet

Seizures have three broad kinds of cause.

KindWhat it meansExamples the sources give
ReactiveThe brain is normal; something else in the body triggers the seizurePoisons, low blood sugar, low calcium, liver or kidney disease
StructuralSomething is wrong in the brain itselfTumours, head injury, inflammation, infection
Idiopathic epilepsyNo cause is found; sometimes geneticDiagnosed after the others are ruled out

Cornell lists among the toxins that can cause seizures “dark chocolate, caffeine, the sugar substitute xylitol, anti-freeze, rat poison and liquor.” The IVETF, an international veterinary epilepsy task force, notes that poisoning is particularly linked to the dangerous kind of seizure: dogs whose seizures are caused by toxins “have a significantly higher risk of developing status epilepticus, particularly as first manifestation of a seizure disorder.”

If your dog could have eaten something, tell the vet straight away. Bring the packet.

→ Xylitol: Where It Hides, and Why Minutes Matter · → Foods That Are Toxic to Dogs, With the Actual Evidence

Age is a clue. Cornell notes that idiopathic epilepsy “usually starts between 6-months-old and 6-years-old”. Dogs having their first seizure when younger than a year are “more likely to have a congenital defect, an intoxication or an infectious disease”, and dogs older than six are “more likely to have a metabolic disorder or a structural brain lesion, like a tumor or a stroke.” The IVETF recommends brain imaging (MRI) and spinal fluid analysis in dogs whose seizures start before six months or after six years, among other groups.

Our note: Sources name breeds with higher rates of epilepsy, but the lists don’t match. We don’t name breeds, because that could suggest other breeds are safe.

5. Will my dog need medication?

Often not after one seizure. Cornell: “If your dog is between 6-months-old and 6-years-old, and their tests are normal, most veterinarians agree antiepileptic drug therapy is not necessary after the first seizure.” Its reasoning is honest: “Your dog may never have another seizure.” And “once an antiepileptic is started, it is generally necessary for life.”

The IVETF recommends starting long-term treatment in dogs with idiopathic epilepsy when any one of these is true:

  • two or more seizures within six months;
  • status epilepticus or cluster seizures;
  • recovery after a seizure that is especially severe, “(e.g. aggression, blindness)”, or lasts longer than 24 hours;
  • seizures getting more frequent, longer or more severe over three intervals (Bhatti et al., BMC Veterinary Research 2015).

Keep a seizure diary from the first one. Date, time, how long, what it looked like, and how long recovery took. Your vet will use it to decide when to treat. Cornell: “your seizure log will help determine when it might be time to start anticonvulsant therapy.”

For dogs with known epilepsy, ask about an emergency plan. The 2024 consensus covers rescue medicine that owners can give at home during a long seizure or a cluster, prescribed by the vet with clear instructions. We are not naming medicines or doses here. If your dog has epilepsy and you don’t have a written plan for a long seizure, ask your vet for one.

Our note: If your dog has epilepsy, ask your vet about home rescue medication. It doesn’t replace going to a clinic.

6. What we could not verify

Commonly saidWhat we found
“A dog can swallow its tongue during a seizure”We found no source that supports it. Every source we read says to keep your hands away from the mouth.
“Put something in the mouth to stop them biting their tongue”Contradicted. The 2026 first-aid guidelines recommend against giving any substance by mouth during a seizure.
“A seizure is only an emergency after three minutes”Not what the consensus says. It uses five minutes. PDSA says to phone at two. We found no source for three.
“One seizure means lifelong medication”Not usually. Cornell and the IVETF criteria suggest waiting, in a young adult dog with normal tests.
“Seizures are painful for the dog”We found no source that addresses this directly. Cornell says the dog “is not aware of their surroundings during a seizure”.

Sources

Always confirm with your vet before acting on anything on this page.