Toxic to cats · Medications

Is Acetaminophen toxic to cats?

Extreme severity No safe amount — No amount is considered safe.

Yes, Acetaminophen is extremely toxic to cats. Even a small amount can be life-threatening, so treat any exposure as an emergency and contact a vet immediately. No amount is considered safe.

Video explainer

Why is acetaminophen toxic to cats and dogs?

Open the video page →

What to do right now

  1. Treat any possible exposure as an emergency, even part of one tablet and even if your cat seems fine. Call your vet or the nearest emergency clinic and go straight in.
  2. Don't make your cat vomit and don't give it anything by mouth. Inducing vomiting at home can cause more harm, and only a vet should do it.
  3. If you gave your cat acetaminophen yourself, tell the vet team straight away and don't give any more.
  4. Bring the package and any remaining pills. Note the strength, any other ingredients, roughly when it happened and how many pills may be missing. Check whether your other pets could have reached them too.
  5. Keep your cat calm and handle it as little as possible, especially if it is breathing hard.
  6. If you need advice on the way, call a pet poison line. In the US: Pet Poison Helpline (855) 764-7661 (a fee applies) or ASPCA Animal Poison Control (888) 426-4435. The call doesn't replace the vet visit.

Go to an emergency vet if

  • Your cat swallowed or was given any acetaminophen or paracetamol, or you think it might have. Go even if it shows no signs.
  • Its gums or tongue look brown, muddy, blue or pale.
  • It breathes fast or with effort, pants, or is weak or very lethargic.
  • Its face or paws swell.
  • It vomits, stops eating, passes dark urine or turns yellow.

Symptoms to watch for

  • Lethargy
  • Swelling of the face
  • Difficulty breathing
  • Brown or blue gums
  • Vomiting
  • Diarrhea
  • Decreased appetite
  • Jaundice

How much is dangerous

No dose of acetaminophen is safe for a cat. Poisoning usually happens at about 40 to 50 mg per kg of body weight, but some cats have shown signs at only 10 mg/kg. A single dose of 95 to 150 mg/kg can cause life-threatening damage to the red blood cells. Part of one tablet can be enough to cause severe poisoning and death, so treat any amount as an emergency.

When signs appear

Signs can start 1 to 4 hours after your cat swallows acetaminophen. Damage to the red blood cells (methemoglobinemia) builds within 2 to 4 hours. Early signs include vomiting, low energy, not eating and swelling of the face and paws. The gums and tongue can then turn brown or muddy, and breathing becomes fast or labored. After a large dose, this can come on within 4 to 6 hours, followed by poor appetite and low energy over the next 24 to 72 hours. Blue gums and serious trouble breathing mean the blood can no longer carry enough oxygen. Liver damage can follow, mainly after large doses, with yellowing of the skin and eyes. Don't wait for signs before you go to the vet.

Why it's dangerous

Cats and dogs have a limited ability to metabolize the drug in the liver, leading to toxic accumulation and damage to red blood cells and the liver.

Toxic compound: Acetaminophen

How vets treat it

Vets first stabilize your cat, with oxygen for breathing trouble and, in severe cases, a blood transfusion. If the exposure was recent, the vet may make your cat vomit and then give activated charcoal to reduce absorption. The antidote is N-acetylcysteine (NAC), which limits damage to the red blood cells and liver. Because cats clear acetaminophen slowly, ASPCA Poison Control advises giving NAC to any cat with signs, however long ago it swallowed the drug. Other care can include IV fluids, vitamin C to help reverse the red blood cell damage, liver support such as SAMe, anti-nausea medicine and frequent blood tests. Cats usually need a hospital stay.

Outlook

The outcome depends on how much your cat swallowed and how quickly treatment starts. Cats that already have severe red blood cell or liver damage have a guarded to poor outlook. Go to the vet even if you found out late: vets still give the antidote to cats with signs.

Where pets are exposed

  • Acetaminophen is called paracetamol outside North America. Common brand names include Tylenol and Panadol, and labels may shorten it to APAP.
  • Many cold, flu, allergy and fever medicines contain acetaminophen, so check the label of any product your pet got into.
  • Products that combine acetaminophen with other drugs, such as aspirin, ibuprofen, caffeine, antihistamines, decongestants, codeine or other opioids. Excedrin and Percocet are examples. The added ingredients can cause their own poisoning.
  • Tablets, capsules, gel caps, melt-away tablets, liquids, powders and suppositories, from children's strengths to extra-strength tablets. Extended-release products can delay absorption.
  • Pills left on a nightstand or dropped on the floor. Pets can also chew through a closed bottle.
  • Well-meaning owners who give Tylenol or children's acetaminophen to a pet in pain, not knowing how dangerous it is, especially for cats.

Prevention

  • Never give a cat acetaminophen or paracetamol, for any reason.
  • Never give a dog acetaminophen unless your vet prescribes it and sets the dose.
  • Don't give your pet any human medicine without asking your vet first. If you think your pet is in pain, book a vet visit.
  • Keep all medicines in a closed cupboard out of reach. Pets can chew through bottles, open low cabinets, jump on counters and get into bags.
  • Take your own tablets carefully. If one drops, shut your pets in another room until you find it. Don't assume a bitter pill will put a pet off.
  • Read the labels on cold, flu, allergy and fever products. Many contain acetaminophen.

Good to know

Cats are much more susceptible than other species due to a decreased ability to metabolize the drug. It is often found in multi-symptom cold and flu products.

Common questions

Can one Tylenol kill a cat?

Yes, it can. Part of one tablet can cause severe poisoning and death, and signs have been seen at doses as low as 10 mg/kg, so no dose is considered safe. Get your cat to a vet straight away, even if it looks fine.

Can I give my dog Tylenol for pain?

Only if your vet prescribes it and sets the dose. Repeated doses can poison a dog at lower amounts than a single large dose, and dry eye can occur even after doses used for treatment. Ask your vet about pain relief made for dogs.

How much acetaminophen is toxic to a dog?

Signs of sudden poisoning are generally not seen unless a dog swallows more than 100 mg per kg of body weight. Liver damage becomes possible at that dose, and red blood cell damage has been reported above 200 mg/kg. Repeated doses lower the threshold. Tablet strengths and combination products vary, so call your vet or a poison line rather than doing the math yourself.

Why is acetaminophen so much more dangerous for cats than dogs?

Cats have very little of the liver pathway (glucuronidation) that safely clears acetaminophen. Their backup pathway is quickly overwhelmed, and toxic by-products build up. A cat's red blood cells are also easily damaged. This turns the blood brown, starves the body of oxygen and causes face and paw swelling, often before liver damage shows.

Is there an antidote for acetaminophen poisoning in pets?

Yes. Vets use N-acetylcysteine (NAC), which helps neutralize the toxic by-products and limits damage to the red blood cells and liver. It is given at the clinic, so don't try to treat your pet at home. The outcome depends on how quickly treatment starts. ASPCA Poison Control advises giving NAC to cats with signs no matter how much time has passed, so never put off the vet visit because you think it's too late.

Are cold and flu medicines dangerous for pets?

Many are. Cold, flu, allergy and fever products often contain acetaminophen, and some add decongestants, antihistamines, caffeine or other painkillers that can cause their own poisoning. Bring the package to the vet so the team can check every ingredient.

Sources

This page is informational and is not veterinary advice. If your pet has been exposed to something risky, contact your vet or an animal poison control line right away.

· How we prepare our guides

More substances toxic to cats

Aspirin Extreme severity Calcipotriene Extreme severity Carprofen Extreme severity Ibuprofen Extreme severity Everything toxic to cats →

Barcode food checks, now on iPhone.

Scan a product's barcode with StrawPaw to spot ingredients that can harm dogs and cats. The app is free to download.

Download on the App Store