Is Acetaminophen Toxic to Cats and Dogs?
Acetaminophen is extremely toxic to cats (one pill can kill) and dangerous to dogs, damaging blood cells and the liver. Call a vet at once.
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 Acetaminophen?
Acetaminophen is extremely toxic to cats (one pill can kill) and dangerous to dogs, damaging blood cells and the liver. Call a vet at once.
Also known as: tylenol, paracetamol, apap, panadol, mapap.
Symptoms to Watch For
🐈 In Cats
- Brown or muddy gums (methemoglobinemia) — develops quickly
- Swelling of the face and paws (edema)
- Difficulty breathing and blue-tinged gums
- Liver damage; can be fatal from a single pill
🐕 In Dogs
- Vomiting and drooling
- Brown or muddy gums (methemoglobinemia)
- Lethargy and weakness
- Liver damage (jaundice) at higher doses
What to Do If Ingested
- Call a veterinarian or poison hotline immediately.
- Note the mg strength and number of pills, and the time.
- 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:
- Any acetaminophen was eaten
- Brown, blue, or pale gums
- Lethargy or difficulty breathing
- Yellowing of the eyes or gums (jaundice)
Frequently Asked Questions
Frequently Asked Questions
Why is acetaminophen so dangerous to cats?
Cats lack the liver enzyme (glucuronosyltransferase) needed to break down acetaminophen, so it builds up rapidly. It converts hemoglobin to methemoglobin, which cannot carry oxygen, turning gums brown and causing swelling of the face and paws. A single regular-strength pill can be fatal to a cat.
Can I give my dog Tylenol for pain?
No. Acetaminophen is not safe to give without explicit veterinary instruction, and overdoses cause methemoglobinemia (brown gums, oxygen starvation) and liver damage in dogs. Use only medications your veterinarian has prescribed at the dose they set.
What should I do if my pet ate acetaminophen?
Call a veterinarian or poison hotline immediately — for cats this is a life-threatening emergency. Note the pill strength (mg) and number eaten and the time. Do not induce vomiting or give home remedies unless a vet tells you to; get to a clinic right away.
Sources
This entry is reviewed against the following authoritative veterinary sources.
- Merck Veterinary Manual — Toxicology
- Pet Poison Helpline — Poisons
- America's Poison Centers — Annual Reports (NPDS)
Last reviewed: 2026-07-11