Ibuprofen (Advil/Nurofen) Poisoning in Cats

What is ibuprofen?

Brand names: Advil, Motrin, Midol and Nuprin

Ibuprofen is an over the counter nonsteroidal anti-inflammatory drug (NSAID) that is routinely used to treat pain, fever and inflammation in people. Poisoning in cats occurs when pet owners self-administer the medication in an attempt to alleviate pain or reduce fever or if cats deliberately ingest tablets.

There is no safe dose of ibuprofen for cats, even a small dose is enough to cause life-threatening damage.

Why can’t cats have ibuprofen?

Many drugs are metabolised by conjugation, and cats lack the major phenol UDP-glucuronosyltransferase (UGT) enzymes, including UGT1A6 and UGT1A9 which means ibuprofen is cleared significantly slower in cats compared to dogs and humans.

Key points

  • Toxicity can cause perforation of the stomach, kidney failure and central nervous system disorders.
  • Symptoms of ibuprofen toxicity include vomiting (with blood), diarrhea, dark-tarry stools, abdominal pain, loss of appetite, incoordination and seizures.
  • Never administer medications to a cat unless prescribed by a veterinarian and if your cat has been exposed to ibuprofen, do not wait and see, seek immediate veterinary help.
  • The earlier treatment starts, the better the outcome.

Effects on the cat

Ibuprofen blocks COX-2 enzymes, which reduce the production of prostaglandins, these hormone-like substances help to protect the lining of the stomach from acid and regulate blood flow and glomerular filtration rate in the kidneys.

When ingestion of ibuprofen occurs, the reduction of prostaglandin results in stomach ulceration and in severe cases, stomach perforation and acute kidney failure.

Signs of ibuprofen poisoning in cats


Gastrointestinal symptoms usually take 2-6 hours to appear.

  • Vomiting (which may contain blood)
  • Abdominal pain
  • Loss of appetite
  • Black, tarry stools


  • Vomiting
  • Diarrhea
  • Lethargy
  • Pale gums
  • Loss of coordination
  • Decreased urine production

Central nervous system:

In severe cases, neurological disorders such as seizures and tremors can occur.


The diagnosis of ibuprofen toxicity is typically based upon a history of recent exposure. The veterinarian will want to know when ingestion occurred as well as how much ibuprofen the cat has had.

Diagnostic workup:

Baseline tests which include complete blood count, biochemical profile and urinalysis will be recommended to evaluate kidney function.

If blood in the vomit or feces has occurred, the veterinarian will want to perform imaging studies to see if the stomach has perforated.


Veterinary treatment is absolutely vital if your cat has ingested ibuprofen. Treatment is aimed at stopping further absorption with rapid and aggressive gastric decontamination as well as supportive care.

  • If ingestion of the medication is recent (within 1-2 hours) and the cat is not displaying neurological signs, the veterinarian will induce vomiting and/or activated charcoal to prevent further absorption. It is not safe to induce vomiting in a cat with neurological signs due to the risk of aspiration.
  • If neurological signs have developed, gastric lavage which involves irrigating the stomach to remove the toxin.
  • Medications to protect the stomach lining such as ranitidine, cimetidine or famotidine for 5-7 days.
  • Anti-emetic medications to control vomiting.
  • Anti-seizure medications such as diazepam or barbiturates if needed.
  • IV fluids to help increase urine production (diuresis), which speeds up the removal of toxins from the blood.
  • A synthetic prostaglandin known as Misoprostol may be given orally, this works to replace the prostaglandin which was inhibited due to the effects of ibuprofen and can help protect the stomach.
  • Surgical repair if the stomach has perforated.
  • While hospitalised, your veterinarian will run regular baseline tests to monitor how your cat’s kidneys are functioning.

What pain medication can I give to my cat?

There are no safe over-the-counter medications for cats. If he is in pain, he will need to have a safe painkiller prescribed by his veterinarian. Never administer painkillers to your cat without veterinary supervision.

Store medicine out of reach of cats.


  • Julia Wilson, 'Cat World' Founder

    Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio