If your dog or cat chewed into a bottle of aspirin or was given a dose, call your veterinarian or an animal poison control center now, even if your pet seems fine. If it was a cat, treat it as an emergency. Use the aspirin calculator to work out the dose from the tablet strength and count.
Enter weight and amount to get an urgency level and next steps.
What to do right now
- Move your dog away from the source and pick up anything left over.
- Find the packaging, label, or plant so you know exactly what was eaten and how much.
- Note your dog's weight and the time it happened.
- Call your veterinarian or an animal poison control center. Do this even if your pet seems normal.
- Do not make your pet vomit unless a professional tells you to.
- Follow the advice you are given, and bring the packaging to the clinic.
How much aspirin is toxic?
Aspirin is a nonsteroidal anti-inflammatory drug (NSAID). It blocks prostaglandins that protect the stomach lining and affects platelets, so bleeding can be prolonged. At high doses it also disrupts how cells make energy, which can lead to fever, fast breathing, a serious acid imbalance, and seizures.
Dogs: veterinary references say the exact toxic dose is not clear and varies between dogs. Stomach and gut signs alone may occur at about 50 mg per kg, toxicity may result from an acute ingestion of about 100 mg per kg, and severe signs are reported across a wide range of 100 to 500 mg per kg. The Merck Veterinary Manual notes that a single ingestion of 450 mg per kg can cause seizures or coma.
Cats: cats clear aspirin very slowly, with a half-life of about 37.5 hours compared with several hours in dogs. Toxicity is reported in cats above 50 mg per kg, and any exposure over 100 mg per kg is considered serious and potentially lethal. Because there is no well-defined safe amount, treat any aspirin a cat eats as an emergency.
| Tablet | 10 lb pet (4.5 kg) | 30 lb dog (13.6 kg) | 60 lb dog (27.2 kg) |
|---|---|---|---|
| One 81 mg low-dose | about 18 mg/kg | about 6 mg/kg | about 3 mg/kg |
| One 325 mg regular | about 72 mg/kg | about 24 mg/kg | about 12 mg/kg |
| One 500 mg extra strength | about 110 mg/kg | about 37 mg/kg | about 18 mg/kg |
These are math examples, not safe amounts. Several tablets add up quickly, and older pets, pets with kidney, liver, or stomach problems, and pets taking other NSAIDs or steroids can be harmed at lower doses.
Aspirin is not the only salicylate in the house. Pepto-Bismol, oil of wintergreen, and muscle-rub creams also contain salicylates. The calculator does not cover them, so call poison control if your pet got into one.
Symptoms to watch for
- Vomiting, sometimes with blood
- Loss of appetite, listlessness, or weakness
- Fast or heavy breathing and panting
- Fever (high body temperature)
- Black, tarry stool or pale gums
- Wobbliness, seizures, or collapse after large doses
Timeline: when signs appear
Aspirin is absorbed quickly, with blood levels peaking about 30 minutes to 3 hours after it is swallowed. Dogs may vomit within about 2 hours. Breathing changes and an acid imbalance can follow over the next hours after a large dose, and ulcers or bleeding problems can show up days later. In cats, aspirin lingers much longer, so effects can last longer too.
Go straight to an emergency vet if
- Your cat ate any aspirin
- Your pet is vomiting (especially blood), panting hard, very hot, weak, wobbly, or having a seizure
- The estimated dose is in the Emergency range on the calculator
- Your pet is older, has kidney, liver, or stomach problems, or also takes another NSAID or a steroid
- A poison control consultation or your vet has told you to bring your pet in
What the vet will do
There is no antidote for aspirin. If the tablets were eaten recently, the vet may induce vomiting and then give activated charcoal. Stomach protectant medicines and anti-nausea drugs are commonly used, and IV fluids help support the body and kidneys.
After a large ingestion, the vet may check blood gases and electrolytes and treat an acid imbalance, monitor liver values and clotting, and recheck kidney values at 24, 48, and 72 hours, as the Merck Veterinary Manual describes. Outcomes are generally good when treatment starts early.
How to prevent it
- Keep aspirin and all pain relievers in closed cabinets, not in purses, nightstands, or on counters.
- Use childproof caps, and never leave pill organizers within reach.
- Never give your pet aspirin or any human pain medicine unless your vet prescribes it and gives you a dose.
- Never give a cat aspirin on your own. Cats can be poisoned by doses that seem tiny.
- Remember hidden salicylates: Pepto-Bismol, wintergreen oil, and muscle-rub creams.
For a room-by-room list you can print, see the pet poison-proofing checklist. Related: My dog ate ibuprofen (Advil, Motrin), My dog ate naproxen (Aleve), and My pet ate acetaminophen (Tylenol).
Enter weight and amount to get an urgency level and next steps.
Frequently asked questions
How much aspirin is toxic to a dog?
Veterinary references report vomiting and stomach upset in dogs from about 50 mg of aspirin per kg of body weight, and severe poisoning across a wide range of about 100 to 500 mg per kg. One 325 mg regular aspirin is about 72 mg per kg for a 10 lb dog and about 24 mg per kg for a 30 lb dog.
How much aspirin is toxic to a cat?
Cats are far more sensitive than dogs. Toxicity is reported above 50 mg per kg, and any exposure above 100 mg per kg is considered serious and potentially lethal. A single 325 mg tablet is over 70 mg per kg for a 10 lb cat. Treat any aspirin a cat eats as an emergency.
My dog ate one baby aspirin. Is that an emergency?
One 81 mg tablet is a small dose for most dogs, but call your vet or a poison control line to confirm, especially for a small or older dog or a dog that takes another NSAID or a steroid.
Can I give my dog aspirin for pain?
Only if your veterinarian tells you to and gives you a dose. Aspirin can cause stomach ulcers and bleeding, and it should never be combined with other NSAIDs or steroids. Never give aspirin to a cat unless your vet prescribes it.