Is paracetamol toxic to dogs?
Yes. Paracetamol, called acetaminophen in the US, has a narrow safety margin in dogs. It can damage the liver within days, and larger doses damage red blood cells so they cannot carry oxygen. A single adult tablet can be a serious dose for a small dog. Pativo treats any ingestion as an emergency: go to a vet now and take the packet.
General information, not veterinary advice. If your pet may have eaten this, contact a vet now; do not wait for signs.
What to do right now
- Go to a vet or emergency clinic now
- Take the packet, including any blister strips, so the vet can count what is missing
- Note the strength per tablet and the earliest time it could have been eaten
- Do not make your dog sick or give any other medicine unless a vet tells you to
Go to an emergency clinic now if
- Your dog ate any paracetamol or a cold and flu product that contains it
- Your dog's gums look pale, brown, grey or blue
- Your dog is breathing fast, panting hard or struggling to breathe
- Your dog's face or paws are swelling
- Your dog is weak, vomiting or has yellow gums, eyes or skin
Who to call
Your own vet first. If they are closed, the nearest emergency or out-of-hours clinic.
In the United States
Both answer 24 hours a day and may charge a consultation fee.
Signs to watch for
| Sign | Usually starts |
|---|---|
| Vomiting, drooling, loss of appetite | Within hours |
| Brown, grey or blue gums; fast breathing | Within hours, larger doses |
| Swelling of the face and paws | Within hours |
| Belly pain, lethargy, trembling | Hours to 1 day |
| Yellow gums, eyes or skin (jaundice) | 1-3 days or more |
| Squinting, eye discharge (dry eye) | Variable |
Why is paracetamol toxic to dogs?
When a dog takes in more paracetamol than its liver can safely process, a toxic by-product builds up. It harms two things: liver cells, and red blood cells, whose haemoglobin is changed into a form (methaemoglobin) that cannot carry oxygen. The Merck Veterinary Manual notes that jaundice and liver damage are more common in dogs than in cats.
VCA Animal Hospitals sums up the pattern: lower doses mainly damage the liver, higher doses also damage red blood cells. Paracetamol can also cause dry eye in dogs, which shows as squinting and discharge.
How much paracetamol is dangerous for a dog?
The Merck Veterinary Manual reports that signs of acute poisoning in dogs are generally not seen below about 100 mg per kg of body weight, and that damage to red blood cells has been reported above 200 mg per kg. Repeated doses over several days can cause poisoning at lower amounts, which matters when an owner has been giving it for pain.
Paracetamol tablets commonly contain 500 mg, so for a 5 kg dog a single tablet already reaches about 100 mg per kg. Weigh this against the strength printed on your packet, but do not use it to decide to stay home: dogs vary, combination products contain other drugs, and Pativo treats every paracetamol ingestion as an emergency.
Check other medicines in the house for paracetamol too. Cold and flu powders, combined painkillers and some allergy and fever products contain it, sometimes under the name acetaminophen or APAP on imported packs.
What will the vet do?
If your dog has no signs and the tablets were eaten recently, the vet may make your dog vomit and then give activated charcoal to reduce absorption. There is a specific antidote that helps the body clear the toxic by-product and protects the liver and red blood cells; it works best when started early.
Dogs with signs are admitted for intravenous fluids, oxygen if the gums are discoloured or breathing is laboured, and medicines to protect the liver. Merck recommends rechecking liver blood tests at 24 and 48 hours and monitoring the red blood cells. The vet may also test tear production if dry eye is a concern.
VCA describes the outlook as excellent when treatment is early. Delayed treatment reduces the chance of a good outcome, and severe cases can leave permanent liver damage or be fatal.
How do I stop it happening again?
- Never give your dog a human painkiller unless your vet has prescribed that exact product and amount.
- Keep all medicines in a closed cupboard, not in handbags, on bedside tables or in pill organisers a dog can chew.
- Pick up dropped tablets straight away; dogs find them quickly.
- Record any medicine your vet does prescribe in Pativo, so the vet report shows exactly what your dog has had.
Other human painkillers are dangerous too: see ibuprofen and similar painkillers in dogs and paracetamol in cats. For signs that need a clinic immediately, see emergency signs.
Questions owners ask
Can I give my dog paracetamol for pain?
No, not unless your own vet has prescribed a specific product and amount for your dog. Many human products combine paracetamol with other drugs, and the margin between a helpful and harmful amount is narrow. Ask your vet for a dog-safe painkiller.
Is paracetamol worse for cats?
Yes. Cats cannot process paracetamol at all, and one tablet can kill a cat. See the guide to paracetamol in cats.
My dog seems fine after eating a tablet. Should I still go?
Yes. Liver damage can develop over several days without obvious signs at first, and treatment is most effective early. Go now with the packet.
Sources
- Merck Veterinary Manual: Toxicoses From Human Analgesics in Animals
- VCA Animal Hospitals: Acetaminophen (Tylenol) Poisoning Alert for Dogs and Cats
- Pet Poison Helpline: Acetaminophen
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