Is Aspirin Toxic to Cats and Dogs?
Aspirin is severely toxic to cats (they clear it very slowly) and moderately toxic to dogs. Overdoses cause ulcers and organ damage. Call a vet.
Potentially life-threatening — treat any exposure as an emergency.
Can cause real harm — call a vet for guidance.
In an emergency, do not wait.
Medical disclaimer: This tool is for general information only and isnot a substitute for veterinary diagnosis or treatment. Toxicity depends on the amount, your pet’s size, and health history. If your pet may have ingested something harmful, contact your veterinarian or a poison control hotline ((888) 426-4435 / (855) 764-7661) immediately — do not wait for symptoms to appear.
What is Aspirin?
Aspirin is severely toxic to cats (they clear it very slowly) and moderately toxic to dogs. Overdoses cause ulcers and organ damage. Call a vet.
Also known as: acetylsalicylic acid, bayer, excedrin, salicylate, bufferin, asa.
Symptoms to Watch For
🐈 In Cats
- Vomiting and drooling
- Stomach ulcers and abdominal pain
- Lack of coordination and "walking drunk"
- Liver and kidney damage (cats clear aspirin very slowly)
🐕 In Dogs
- Vomiting, sometimes with blood
- Stomach ulcers and abdominal pain
- Rapid breathing and fever
- Kidney injury with larger doses
What to Do If Ingested
- Note the mg strength and number of pills eaten, and whether it was plain or buffered.
- Call a veterinarian or poison hotline for guidance.
- Do not induce vomiting unless a vet directs it.
Steps apply to both cats and dogs. When in doubt, call a vet or poison hotline before acting.
When to Call the Vet Immediately
Call your veterinarian or a poison control hotline right away if you notice any of these:
- A large amount or several doses were eaten
- Vomiting, especially with blood
- Rapid breathing, panting, or fever
- Changes in urination or lethargy
Frequently Asked Questions
Frequently Asked Questions
Why is aspirin more dangerous to cats than dogs?
Cats lack the liver enzyme (glucuronosyltransferase) that breaks down aspirin, so it stays in their body for around 40 hours versus about 8 hours in dogs. Even small repeated doses build up and cause poisoning. Never give a cat aspirin without veterinary direction.
My vet told me to give my dog aspirin — is it safe?
Only at the specific dose and schedule your veterinarian prescribed. Aspirin can be used short-term in some dogs, but overdoses cause stomach ulcers and kidney injury, and it interacts with many other medications. Never exceed the prescribed dose, and call your vet if vomiting or belly pain occurs.
What are the signs of aspirin poisoning?
Vomiting (sometimes with blood), diarrhea, belly pain, panting, and fever, with lack of coordination and lethargy in serious cases. Cats may stumble or seem "drunk" because the drug accumulates. Call a vet if you see these signs.
Sources
This entry is reviewed against the following authoritative veterinary sources.
Last reviewed: 2026-07-11