Toxic to dogs · Medications

Is Acetaminophen toxic to dogs?

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

Yes, Acetaminophen is highly toxic to dogs. Exposure can cause serious illness and needs prompt veterinary attention. 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. Call your vet, an emergency clinic or a pet poison line right away, even if your dog seems fine. Early treatment gives the best outcome. In the US: Pet Poison Helpline (855) 764-7661 (a fee applies) or ASPCA Animal Poison Control (888) 426-4435.
  2. Don't make your dog vomit and don't give any home remedy unless a vet or poison expert tells you to. Vets do make dogs vomit, but only early and at the clinic.
  3. Bring the package or bottle and any remaining pills. Note the strength (mg per tablet or per mL), any other ingredients such as an antihistamine, caffeine or a decongestant, when it happened and your best count of how many are missing.
  4. Have your dog's weight, age and current medicines ready, and check whether your other pets could have reached the pills too.
  5. If your dog vomits on the way, look for pill pieces and keep the vomit or describe it to the vet team.

Go to an emergency vet if

  • Your dog shows any sign of distress after a possible exposure. Go straight to your vet or the nearest emergency clinic.
  • Its gums look pale, brown, muddy or bluish, or it is breathing hard, panting heavily or weak.
  • Its face or paws swell up.
  • Its gums, eyes or skin turn yellow, or it keeps vomiting, stops eating or seems confused.
  • It swallowed a large amount or a combination cold or flu product, or it was given repeated doses.

Symptoms to watch for

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

How much is dangerous

Dogs are much less sensitive than cats, but acetaminophen can still poison them. Signs of sudden poisoning are generally not seen unless a dog swallows more than 100 mg per kg of body weight, and from that dose liver damage is possible. Red blood cell damage (methemoglobinemia) has been reported at doses above 200 mg/kg. Repeated doses, such as acetaminophen given over several days, can poison a dog at lower amounts, and serious liver failure in dogs mostly follows repeated high doses or swallowing many tablets. Dry eye can occur even after doses used for treatment. Tablet strengths and combination products vary, so let your vet or a poison line work out the risk rather than doing the math yourself.

When signs appear

Early signs include vomiting, not eating, belly pain and a dull mood. When the liver is affected, dogs usually become ill within 24 hours, with poor appetite, vomiting and diarrhea. Liver failure can then progress over 36 to 48 hours to confusion or other nervous system signs, then to coma and death within 72 hours. Other signs include swelling of the face and paws, yellowing of the gums, eyes or skin, and brown urine. Large doses can damage the red blood cells, causing weakness, pale, brown or bluish gums, trouble breathing and heavy panting. Some dogs get sudden dry eye, with squinting, eye discharge and eye pain.

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

If your dog swallowed it recently, the vet may make it vomit and then give activated charcoal to reduce absorption. The antidote is N-acetylcysteine (NAC). It helps the body neutralize the drug's toxic breakdown products and limits damage to the liver and red blood cells. It is given as a first, larger dose followed by repeat doses. Supportive care can include IV fluids, anti-nausea medicine, oxygen and, if the red blood cells are badly damaged, a blood transfusion. Vitamin C may help reverse the red blood cell damage, and SAMe may support the liver. The vet checks the blood for red cell damage, rechecks liver enzymes at 24 and 48 hours, and may do a tear test for dry eye.

Outlook

The outlook is excellent when treatment starts early. How a dog does depends on how much it swallowed and how soon treatment starts, and severe liver failure can be fatal.

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 dogs

Camphor High severity Lunesta High severity Methylphenidate High severity Aspirin Extreme severity Everything toxic to dogs →

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