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What is it?

Vomiting is defined as ‘the forceful evacuation of stomach contents beyond the mouth’. It can be undigested or part-digested food, or the cat can continue to vomit when the stomach is empty, producing a yellow-brown frothy bile. The cat may show signs of nausea, for example drooling, licking of the lips, swallowing and retching, and hiding away.

It is important to note the difference between vomiting and regurgitation. Vomiting requires contraction of the abdominal muscles. Regurgitation requires little or no effort and the cat may produce a tube shape of undigested food with some mucus. Regurgitation may be caused by disease of the oesophagus such as a widening (megaoesophagus) or narrowing (a stricture or tumour), difficulty breathing, coughing, or a foreign body.

Why do cats vomit?

There are a very wide range of possible causes. To help understand them, we can describe the vomiting as either primary or secondary, and as either acute or chronic.

Primary vomiting is caused by diseases affecting the stomach and gut itself, for example a foreign body, a tumour, or inflammatory bowel disease.

Secondary vomiting means that the cause is not from the stomach and gut itself, for example ingestion of a poisonous substance which stimulates the vomiting centre in the brain.

Acute vomiting develops suddenly and rapidly; and can be very intense. Some common causes include:

  • Foreign body obstruction (cats may eat strings or ribbon, which can lodge in the intestines and cause life threatening damage - a ‘linear’ foreign body). Other foreign bodies may be parts of toys, or anything that is not food
  • Poisoning - in particular antifreeze, paracetamol, lilies, chocolate, or onions (all can cause very serious illness ranging from anaemia to kidney damage)
  • Parasites
  • Intussusception (the gut becomes trapped within itself)
  • Sudden change in diet, or scavenging
  • Gastritis - an inflamed stomach lining
  • Acute liver disease
  • Viral diseases
  • Acute kidney disease
  • Urinary obstruction
  • Heat stroke
  • Chronic vomiting is vomiting that occurs for 3 weeks or longer. Some common causes include:

  • Chronic kidney disease
  • Overactive thyroid (hyperthyroidism)
  • Viral diseases - e.g. viral enteritis (panleukopenia), Feline Immunodeficiency Virus (FIV), Feline Leukaemia (FeLV)
  • Diabetes
  • Pancreatitis
  • Pyometra - infection of the uterus. Relatively infrequently seen in cats, but can happen in entire (unspayed) females
  • Severe constipation
  • Tumours such as intestinal lymphoma. Tumours may grow and obstruct the bowel, causing vomiting
  • Inflammatory bowel disease
  • Hair balls

  • When is vomiting an emergency?

    Your cat should be seen by a vet as soon as possible if:

  • The vomiting is continuous and lasts more than 24 hours
  • You suspect that something poisonous has been eaten by your cat
  • You suspect that something that is not food has been eaten by the cat that may be stuck in the gut
  • You see a thread in your cat’s back passage or mouth (this is often a life-threatening emergency)
  • Your cat is unable to keep water down, or is drinking excessively
  • Your cat is weak or depressed, and not wanting to eat
  • Your cat’s gums are pale or yellow
  • There is blood in the vomit, or something in the vomit that is not food
  • Your cat is showing any other unexplained symptoms, such as wobbliness, weakness, changes in gum colour, or altered behaviour.

  • Why is it important?

    Occasional vomiting may be nothing to worry about, however some causes of vomiting can be life threatening, and it is important that the cat receives prompt veterinary attention and treatment.

    How does the vet know what is going on?

    Your vet will talk to you about when the vomiting started, how long it has been going on for, and whether there are any obvious causes. There are many different causes of vomiting, so diagnostics such as blood tests, radiographs (X rays), ultrasound imaging, or urine testing may be required in addition to a full physical examination.

    What can be done?

    Mild vomiting that lasts for less than 24 hours may not be anything to worry about; withholding food for 12 hours (allowing full access to water) and reintroducing small amounts of easily digestible food (commercially available and specially formulated for sensitive guts, or a good protein source such as white fish or chicken) will usually stop the vomiting in a mild gut upset or gastritis. Sometimes cats may eat their food too quickly resulting in occasional vomiting. Hairballs can be managed with laxatives, regular grooming and a special diet.

    More serious vomiting disorders will require more complex treatment, depending on the diagnosis:

  • A foreign body or obstruction of the bowel by a tumour may require surgery.
  • Inflammatory bowel disease can be managed medically and with a suitable diet.
  • Some cats may require a prescription digestive support diet to manage their vomiting.
  • If the cat is dehydrated or has eaten something poisonous then it may require a period of hospitalisation to treat with a drip/intravenous fluids.
  • If a tumour is diagnosed, especially if it is blocking the gut, surgery or chemotherapy might be needed; in some cases, it may be kinder to euthanase the cat (put them to sleep).

  • How can I protect my pet?

  • Keep things poisonous to cats away from their environment
  • Feed an appropriate balanced diet to your cat
  • Regularly deworm your cat especially if they are outdoors and hunting.
  • A cat who is vomiting continuously should always be seen by a vet as soon as possible.