Some things are extremely toxic for one species but less so for another. Paracetamol is a good example of this. We can take paracetamol safely at the recommended doses, and so can our canine companions (if dosed correctly for their species, under the guidance of a vet). However, cats cannot and under any circumstance you must never be tempted to give your feline friend some of your medication.

In this blog, we’ll explore why paracetamol is bad for cats and what you can expect if your pet suffers from poisoning.

Please note – paracetamol is extremely dangerous for cats so if you suspect they have eaten even a tiny bit, then call your vet straight away.

What is paracetamol?

Paracetamol (known as acetaminophen in some countries) is often purchased as an over-the-counter medication and used as pain relief in people. It also has antipyretic (temperature-reducing) properties making it useful if there is a fever. It can be found in a variety of forms, including tablets, capsules and liquids and is sold by many different brands. Paracetamol even comes in formulations with other ingredients such as decongestants, codeine and caffeine.

Most people will take paracetamol at some point for a whole array of coughs, colds, aches and pains, so we are well used to having it in our homes. However, you should never give it to your cat and you should always keep it out of reach from your pets to stop accidents from happening.

Why is paracetamol poisonous to cats?

Cats simply can’t tolerate paracetamol. They lack the ability to metabolise and break down paracetamol safely, meaning toxic compounds start to build up in the body. This causes serious damage to the red blood cells, affecting their ability to carry oxygen around the body. The main issue is that the haemoglobin in their red blood cells becomes changed to methaemoglobin which is much less effective at oxygen transportation (and brown, rather than red). Over a matter of hours, damage to other organs, including the liver, can also occur.

Paracetamol is absorbed rapidly once ingested, so you must get your cat to a vet immediately. Don’t wait and see if symptoms develop, early treatment is crucial.

Are there signs of paracetamol poisoning in cats?

Clinical symptoms of paracetamol toxicity may begin as early as 4 hours after ingestion, and almost always within 24 hours. Cats that have ingested paracetamol may show the following symptoms –

  • Brown-coloured gums and tongue (mucous membranes) are characteristic features of this condition.
  • Weakness
  • Changes in appetite
  • Increased heart rate
  • Changes in breathing, faster or more laboured
  • Vomiting
  • Depression
  • Collapse
  • Death

What should I do if my cat has eaten paracetamol?

You should immediately stop your cat from consuming any more paracetamol and call your vet. This may mean seeing your regular vet in the daytime, or your practice’s out-of-hours provider overnight, but either way, your cat needs seeing urgently. Do not wait to see if symptoms develop as your cat could become extremely sick.

What treatment will my vet need for paracetamol poisoning?

Your vet will start by examining your pet to assess if any clinical symptoms have started yet. They will look at their mucous membranes, listen to their heart rate and breathing and check their temperature.

Decontamination is the next step. If your cat has only recently eaten paracetamol, then your vet will either try and induce vomiting and/or will suggest that they have their stomach flushed. They may also administer activated charcoal. This is all aimed at reducing any further paracetamol from being absorbed.

There is also an antidote that can be administered to counteract any of the drug that is already in your cat’s system, acetylcysteine. This can make a big difference to your cat’s prognosis if administered early enough, ideally before any symptoms have begun.

Depending on your cat’s other symptoms they may also require oxygen supplementation to help with breathing, intravenous fluids to counteract dehydration and help stabilise blood pressure and antinausea medication. In severe cases, a blood transfusion may be required.

Your vet will usually suggest blood tests to check your cat’s red blood cell levels and to assess other things too like liver and kidney function which can help monitor their condition and inform the treatment plan.

Your cat will need to be hospitalised during this period for supportive care.

Will my cat be ok if they have eaten paracetamol?

If veterinary treatment is sought early this will greatly improve your cat’s prognosis. Treatment success depends on how much paracetamol your cat has eaten and how much time has passed since your cat ingested it. If your cat receives immediate appropriate medical care then there is a good chance of survival, however, any delays may end up in long-term organ damage or even death.


No amount of paracetamol is too little to worry about. So if your cat has eaten any amount at all, contact your vet immediately. If treatment is started immediately before your cat develops any clinical symptoms, then they have a much better chance of survival. But if veterinary care is delayed then the damage could be irreversible.

If you think your cat is unwell or in pain, you must always speak to your vet rather than reaching for the paracetamol from your bathroom cabinet.

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