Paracetamol is a human medication that is highly toxic to cats. Even small amounts can cause serious problems. Speak to a vet straight away if you think your cat may have ingested paracetamol.

Paracetamol is also known as acetaminophen. It is the ingredient in products like Calpol, Panadol, and Tylenol, and is a part of many flu medicines. In cats, as little as 10 mg/kg may cause serious negative effects. Toxic substances will be produced in the body, causing damage to red blood cells, the liver, and other organs. Symptoms may start within 1-2 hours or may take up to two days to develop. Immediate, intensive care is required and recovery may be prolonged.

What is paracetamol intoxication in cats?

Humans and dogs have enzymes in their liver that process and eliminate substances like paracetamol, preventing them from causing intoxication unless they are ingested in very high doses. Cats have very few of these enzymes, putting them at risk of serious problems even with ingestion of small amounts of some drugs.

Paracetamol will cause two major problems in cats:

• Red blood cells will become unable to distribute oxygen throughout the body, which disrupts every organ in the body, especially the heart and brain.

• Acute liver damage, which can lead to more toxins being produced, and disrupts metabolism and the functions of other organs

• Many cats will also develop swelling of their face and paws.

Symptoms of paracetamol intoxication in cats

Symptoms will depend on the organs being most affected.

Red blood cell damage:

• Dark or bluish gums and tongue

• Fast breathing

• Extreme exercise intolerance

• Brown urine

• Collapse

Liver damage:

• Lack of appetite

• Vomiting

• Lack of energy

• Tummy pain

• Jaundice (yellow tinge to the skin, gums or the white part of the eyes)

• Abnormal behaviours, like pacing, disorientation of pressing the head against a wall

• Seizures

• Coma

Another common symptom is swollen face, head and paws.

Cats at higher risk for paracetamol intoxication

All cats have a high risk of paracetamol intoxication if they ingest it, either directly or by grooming it off their coat.

Diagnosis of paracetamol intoxication in cats

Paracetamol intoxication is usually diagnosed based on known ingestion and observed symptoms, as there is no readily available test to confirm it.

Routine blood tests that check red blood cells and signs of liver damage will usually detect the consequences of paracetamol intoxication and allow for monitoring of progression.

Veterinary treatment of paracetamol intoxication in cats

• The first and most important step in treating intoxication is stopping the poison from entering the blood and organs. If paracetamol may have been ingested, the stomach should be emptied as quickly as possible, ideally within 30-90 minutes. This can be done by injection or by pumping the stomach under anaesthesia.

• The next step is administering activated charcoal. This sticks to paracetamol in the gut and prevents it from being absorbed. Large amounts are needed, so a high-strength veterinary product is best. This may be needed for up to three days.

• Cats are likely to need intensive hospital care for 1-3 days to control the symptoms and help the body eliminate toxic by-products.

• Supplemental oxygen by mask or oxygen chamber may help prevent vital organs from becoming critically oxygen deficient.

• A medication called N-acetylcysteine can be used as an antidote, as it helps the body eliminate the toxic by-products of paracetamol and reduces some of the damage they cause. This often needs to be administered repeatedly for up to two days.

• Medications that protect the liver from oxidative damage, like SAMe and silybin, help contain liver damage.

• Ascorbic acid may help red blood cells recover and may have some protective effect on the liver.

Home treatment of paracetamol toxicity in cats

Always contact a vet for advice immediately if you think your cat has ingested paracetamol. Most cases require emergency care.

Cats that overcome a toxic ingestion of paracetamol may require liver support for some time. This may include a special diet for liver patients and medication such as SAMe and silybin.

Prevention of paracetamol intoxication in cats

• Always store medications in a safe place and out of reach of your pets, even if they don’t look appetising.

• Cats may ingest significant amounts of toxins by grooming themselves. If your cat has liquid medicine on their fur, use a buster collar or something similar to prevent grooming. Remove as much of the medicine as you can and contact a vet immediately for further advice.

• Be very vigilant when giving medicines with food if you have more than one pet.

When to worry about paracetamol intoxication in cats

Always contact a vet for advice immediately if you think your cat has ingested any paracetamol. Speak to a vet for advice if your cat is:

• Vomiting

• Not eating anything

• Drooling excessively

• Behaving abnormally

If your cat develops any of the following symptoms, see a vet as soon as possible:

• Weakness or collapse

• Trouble breathing

• Seizures

• Vomiting and/or diarrhoea with blood

• Abnormal colour in their gums or the white of their eyes