Acute Vomiting in Cats

What is acute vomiting?

Acute vomiting is the sudden onset of vomiting which may occur once only or continue until the contents of the stomach are completely emptied. It is in contrast to chronic vomiting which can intermittently continue for weeks or months.


There are several possible causes of acute vomiting in cats, some benign, others life-threatening. It is up to us, as the pet owner to assess the situation and if at all in any doubt, see a veterinarian.


  • Intestinal blockage – Eating a cooked bone, or a non-food object such as wool (known as pica), hairballs, heavy tapeworm infection, twisting of the intestine, telescoping of the intestines, umbilical hernia resulting in the intestines protruding through the abdominal wall.
  • Gastroenteritis – Inflammation of the stomach and intestines which may be due to bacterial infection, intestinal worms, and dietary indiscretion.


  • Eating too fast.
  • Sudden changes in diet – Many cats can be quite sensitive to new foods if you are planning to change your cat’s type of food, do so gradually over a few days.
  • Poisoning – There are many substances toxic to cats, ingestion may occur due to dietary indiscretion, deliberate poisoning or when a well-meaning pet owner administers medications or supplements not suitable for cats. Toxins can include plants, drugs, metals, household cleaners, insecticides, chocolate.
  • Food poisoning – This may be due to dietary indiscretion or food which has spoiled or been left out too long.

Infections or parasites:

  • Feline panleukopenia – A severe and highly infectious viral infection that destroys white blood cells, which are cells of the immune system responsible for fighting infection.
  • Intestinal parasites Roundworm, in particular, can be a cause of acute vomiting, particularly heavy infestations in kittens.
  • Coccidiosis – A protozoal infection caused by a single-celled parasite. Most adult cats carry coccidia without signs of illness, kittens under six months and cats who are immunocompromised are at the most significant risk of developing symptoms.


  • Certain medications – Certain antibiotics and painkillers.
  • Heatstroke.
  • Pancreatitis – Inflammation of the pancreas which has several causes including certain viral infections, high fats in the blood, toxoplasmosis, trauma, fatty diet and obesity.
  • Acute metritis – Inflammation of the lining of the uterus in a female cat who has recently given birth.
  • Stomach ulcer – These can develop over time or quickly depending on the underlying cause which may include certain medications such as aspirin, ingestions of poisons, corticosteroids, pancreatitis.
  • Acute kidney failure – Due to shock, poisoning, urinary blockage, infection, certain medications, heatstroke, and trauma.
  • Hepatic lipidosis – A serious and life-threatening disease that can occur if a cat stops eating. The liver breaks down fat to use as an alternate energy source; however, it is not very efficient at processing fat, which builds up, interfering with the liver’s ability to function.

Accompanying symptoms

Vomiting is the predominant sign; other symptoms may include:

When to see a veterinarian

Almost all cats have the occasional vomit which comes out of the blue. If it is only once, and your cat appears to be otherwise well, a wait and see approach may be all that is required. Cats who are repeatedly vomiting are at risk of not only the cause of the vomiting but also dehydration. Kittens are especially vulnerable.

You should take your cat to a veterinarian as soon as possible if the following occur:

  • Vomiting lasting several hours
  • Your cat is under six months of age
  • Your cat also has diarrhea
  • Black tarry stools
  • No defecation
  • If you suspect he has ingested something poisonous or medications he should not have had
  • Blood in the vomit
  • No appetite
  • Pain
  • Fever
  • Swollen or painful abdomen
  • Hunched over
  • Dehydration (signs include sunken eyes, tacky or dry gums, lethargy and increased skin tenting)
  • If you are at all worried, doing something, and getting reassurance is better than worrying


Your veterinarian will perform a complete medical examination of your cat and obtain a medical history from you, which will include:

  • Recent food and medications your cat has consumed?
  • If the cat may have ingested any poisons or household plants or got into anything he shouldn’t have (such as the garbage bin)?
  • When did symptoms first develop?
  • Any recent illness your cat has had?
  • How often the cat has vomited
  • Any accompanying symptoms?

If possible, bring along a sample of your cat’s vomit for the veterinarian to examine.

Diagnostic workup:

Biochemical profile, complete blood count, and urinalysis. These can paint a picture of your cat’s overall health, evaluate the organs and look for signs of infection or inflammation, dehydration and electrolyte imbalances.

The physical examination, accompanying signs and the history from you may help your veterinarian narrow down a possible cause. Depending on his index of suspicion, he may also want to run the following tests:

  • X-ray or ultrasound to evaluate the organs, look for signs of blockage, inflammation, retained placenta in female cats who have recently given birth and other abnormalities.
  • Faecal examination to look for parasites.
  • Endoscopy – A long plastic tube with a camera is inserted through the mouth and passed down the esophagus for your veterinarian to evaluate the esophagus and stomach. Biopsies may be taken at this time.


The goal of treatment is to address the underlying cause as well as provide supportive care while the cat recovers.

For transient or mild vomiting where no other symptoms are present, the veterinarian may recommend the cat fast for 12-24 hours. After this time, switch to a bland diet of boiled chicken and rice to let the gastrointestinal tract recover. Water is still to be available at all times.

  • Bacterial infections: Antibiotics.
  • Blockages or foreign objects: Surgery.
  • Poisoning: Gastric decontamination and activated charcoal to bind to remaining toxins. Supportive care.
  • Intestinal worms: Anti-parasitic medication to kill the worms.
  • Pancreatitis: Treat the underlying cause and supportive care, which will include pain relief.
  • Hepatic lipidosis: Intensive nutritional support and supportive care.
  • Stomach ulcers: Medications to reduce stomach acid and to form a protective coating over the stomach wall which will prevent further damage to the ulcer. Your cat will be fed a bland diet to your cat until the ulcer has healed.
  • Heatstroke: Bring down the cat’s body temperature, oxygen therapy, cortisone injections to reduce swelling in the throat and careful monitoring of the kidneys and liver.

Supportive care:

Fluids to treat dehydration and correct electrolyte imbalances, nutritional support and anti-emetic medications such to control vomiting.


Avoid switching diets too suddenly, if you want to change the type of food your cat eats, start by adding a small amount of the new food to his regular food, gradually increasing the new food while decreasing the old. This should take 5-7 days.

Don’t feed your cat human food; many are either poisonous or too rich for cats to eat.

Make sure you have a secure bin that your cat can’t get into. Dispose of uneaten food properly.

Don’t give your cat any medications (human or veterinary) unless you have been told to do so by your veterinarian.

If you have a cat who vomits immediately after eating it may be due to eating too fast, in which case, he should be switched to several smaller meals a day. In cases of repeated vomiting, he may have megaesophagus, which will need investigation.

Never allow your cat to eat cooked bones which can splinter and cause intestinal obstruction as well as trauma.

Ensure all houseplants are safe for cats.

Ensure all flower bouquets are safe for cats. If in doubt, place the flowers in a room your cat can’t access. Lilies, in particular, are a common flower in bouquets and they are lethal to cats.

Print or download PDF.