How Safe is Paracetamol for Dogs?

Paracetamol contains the active ingredient acetaminophen, and can be toxic for dogs if administered in larger doses. Paracetamol is fatal in cats, but may be given to dogs under strict veterinary supervision.


Paracetamol is also known as acetaminophen, and is marketed as Tylenol and other brand names. The use of paracetamol is recommended in canines for:

  • Respiratory infections
  • Fever
  • Pain management (especially bones and muscles)
  • Inflammation

Paracetamol is rarely recommended for use in dogs, as there are other drugs that have similar effects and are not as damaging for the liver. Paracetamol has been formulated for use in humans, but can be used in canines with great caution. Paracetamol can be toxic in humans and may lead to liver damage, while in dogs, an overdose can be deadly.

Paracetamol is toxic for cats, as the bodies of felines don't produce an enzyme, the glucuronyl transferase, which is necessary to assimilate the drug. Dogs produce this enzyme, but the drug may influence the liver function and may also cause liver damage.

Paracetamol Toxicity

Paracetamol can cause liver toxicity if administered to dogs in high doses. A dog that has had an overdose of paracetamol will display a few symptoms such as:

  • Vomiting
  • Seizures
  • Discoloration of the tongue and pale gums
  • Lack of coordination
  • Drooling
  • Confusion

The dog may not display these symptoms until after the acetaminophen has entered his system. You should get immediate help, as the dog may die within a few hours after the ingestion of paracetamol. Paracetamol will cause liver failure, which is fatal. The dog should receive activated charcoal, which should absorb the ingested paracetamol. The vet will also apply liquid therapy.

A paracetamol overdose may be treated with an antidote, known as acetylcysteine (or N-acetylcysteine or NAC), which can prevent liver damage and allow the body to recover. However, the antidote is not always administered in time and to prevent death, a liver transplant may be needed. Liver transplant in dogs can be complicated and may not be performed by all vets.

Some dogs may die from the formation of methaemoglobin, caused by paracetamol. In other cases, death may occur due to hemolythic anemia, due to the formation of Heinz bodies that limit the transportation of oxygen in the blood and can cause asphyxiation.

Paracetamol Dosage in Dogs

Paracetamol is restricted in use for dogs. When used, the vet will determine a precise dose, so that the dog's liver is not affected. The dose will depend on the dog's size and age.

Paracetamol Contraindications

If the dog has a liver condition, paracetamol is strictly forbidden. The components of paracetamol influence the liver function and if the liver is damaged, the drug may be fatal. A dog that is under narcotic or analgesic medication shouldn't take paracetamol.