Cat Vomiting – Causes and Treatment of Vomiting in Cats

Causes of cat vomiting   When to see a veterinarian   How is the cause of vomiting diagnosed?   How is vomiting treated?

Vomiting in cats

Medically known as emesis, vomiting is a chain of events of which the end result is the forceful ejection of the stomach contents. It is one of the most common reasons cat owners take their cat to the veterinarian.

There are a number of possible causes  of vomiting cats.  It may be acute (sudden onset), chronic (over a period of time) or sporadic (coming and going). Acute vomiting is defined as vomiting which has been present for less than one week and is usually the result of a single insult to the stomach and is self-limiting,  chronic vomiting lasts longer than a week, can be intermittent or persistent in nature.

Causes of vomiting in cats:

The most common cause of vomiting is swallowing hair or other indigestible products (such as grass) which cause irritation to the stomach, this is known as irritative gastritis.

Eating food too fast is another extremely common reason why cats vomit. You may notice your cat race to eat his food only to vomits it back up thirty seconds later, the vomit looks and smells just like cat food.

Vomiting can very loosely be divided into four groups.

Gastrointestinal disorders

  • Acute metritis – Inflammation of the lining of the uterus in cats post birth.
  • Cancer.
  • Coccidiosis – Infection with a protozoa (single celled organism) known as coccidia.
  • Feline panleukopenia – Viral infection caused by the parvovirus.
  • Gastritis – Inflammation of the stomach.
  • Gastric ulcer – A stomach ulcer may be due to too much stomach acid, certain medications, certain poisons, parasites and helicobacter pylori.
    Helicobacter pylori
  • Hairballs.
  • Inflammatory bowel disease – A number of related diseases caused by different types of inflammatory cells invading the intestinal wall.
  • Intestinal obstruction and foreign bodies – Cats aren’t as prone to swallowing miscellaneous objects as dogs are, however, accidental ingestion may occur when playing. Common objects include hair bands, string, sewing thread etc.
  • Salmonella – Bacterial infection caused by salmonella.
  • Worms – Parasitic worms, usually roundworms can cause vomiting in cats.

Hormonal (endocrine) diseases

  • Addison’s disease – Deficiency of corticosteroids.
  • Feline diabetes – Endocrine disorder caused when the body doesn’t produce enough insulin or the cells are unable to respond to insulin, starving the cells of glucose.
  • Hyperthyroidism – Usually caused by a hormone producing benign tumour of the thyroid gland.

Systemic diseases

  • Kidney disease – This may be chronic or acute. Acute kidney disease can occur if your cat has ingested a toxin. Chronic kidney disease is common in middle-aged to senior cats as a slow and gradual decline in kidney function occurs.
  • Liver disease – There are several causes of liver disease in cats, including hepatic lipidosis which develops when a cat becomes anorexic (stops eating), the body begins to break down fat to use for energy which is sent to the liver, which can overwhelm the liver, ingestion of toxins, liver inflammation, tumours and portosystemic shunt, which is a congenital disorder (present at birth). Portosystemic shunt is seen most often in cats under 12 months of age.
  • Pancreatitis – Inflammation of the pancreas.


  • Foreign body.
  • Certain medications (NSAIDS, antimicrobials, and other medications).
  • Heat stroke.
  • Morning sickness.
  • Motion sickness.
  • Poisoning.
  • Ruptured bladder – Usually caused by trauma or urinary blockage.
  • Twisted or obstructed bowel.

When should my cat be taken to a veterinarian?

An isolated incident of vomiting where the cat shows no other signs of illness is not uncommon and generally doesn’t necessitate a trip to the vet.

If the vomiting is more than an isolated incident, or if you notice other symptoms along with the vomiting, then a trip to the veterinarian is necessary.

You should seek veterinary attention:

  • If your cat vomits repeatedly.
  • If your cat has diarrhea.
  • If the vomit is foul smelling.
  • If your cat acts lethargic.
  • If you suspect your cat has ingested a poison or toxin.
  • If the vomit contains blood (hematemesis).
  • If the cat appears listless and unwell.
  • If the abdomen is bloated.
  • If your cat is drooling.

How is vomiting diagnosed?

If possible, when you take your cat to the veterinarian, bring along a sample of the vomit. This will assist the vet to determine the underlying cause of the vomiting.

Your veterinarian will perform a complete physical examination of your cat and obtain a medical history, including possible exposure to toxins and dietary history (including possible dietary indiscretions) any medications your cat may be on. The type of material vomited, frequency, age of your cat, and other clinical signs your cat is displaying can all help your veterinarian. He will also need to differentiate between vomiting, regurgitation, and coughing, all of which can be similar.

Being able to assess the vomiting will assist your veterinarian. He may ask about the type of vomiting your cat has been experiencing, such as:

Type of vomiting Possible cause
Acute vomiting This could suggest a number of problems, such as consumption of food that has spoiled or the ingestion of a non-food item, such as grass or hairballs, salmonella, pancreatitis, food intolerance, heat stroke, sudden changes in diet and poisoning.
Chronic vomiting Diabetes, kidney disease, hyperthyroidism, liver disease, tumours, food intolerance.
Sporadic vomiting This is occasional vomiting that is not related to eating. The cat vomits on and off; there may be other symptoms, such as loss of appetite, lethargy, and listlessness. Sporadic vomiting may suggest kidney or liver disease, heavy worm infestation, diabetes, or gastritis.
Projectile vomiting This is the forceful ejection of vomit which goes a considerable distance. It could suggest an intestinal blockage or tumour.
Vomiting clear fluids This may suggest an intestinal obstruction or in cases of prolonged vomiting, the stomach contents may have already been vomited and all that remains is liquid.
Vomiting foreign objects Hairballs, pieces of cloth, etc.
Vomiting blood This could indicate a break in the intestinal lining, often caused by a foreign body. Tumours and ulcers are other causes of blood in the vomit. Bright red vomit is indicative of bleeding from the esophagus, dark blood suggests bleeding from the stomach which could be due to an ulcer.
Vomiting undigested food The likely cause is megaesophagus, eating too fast or playing too soon after eating or a food allergy/intolerance.
Fecal vomiting This suggests an intestinal obstruction.
Vomiting white foam Vomiting foam is an indication your cat has an empty stomach and all that is left is water and gastric juices.
Vomiting brown liquid This could be due to bile, having eaten something brown coloured such as chocolate (which is toxic) or bleeding somewhere in the gastrointestinal tract.
Vomiting bile (yellow/green fluid) The cat has an empty stomach and all that is left is water and gastric juices other causesd include pancreatitis or gastritis.
Motion sickness Vomiting only occurs when the cat is travelling.
Vomiting worms Long, thin, white, spaghetti like worms in the vomit are a sign of roundworm infestation. From time to time a cat may also vomit up a tapeworm, which is long, white/cream with a ribbon like appearance and segmented.

He will wish to perform some tests, some of which may include:

  • Complete blood count to check for parasites, anemia, or infection.
  • Biochemical profile to evaluate organ function and levels of potassium in the blood.
  • Urinalysis to evaluate kidney function and look for signs of infection.
  • Fecal examination to check for parasites.
  • Total T4 may be performed on an older cat to evaluate for hyperthyroidism.
  • FeLV/FIV tests.
  • Abdominal X-rays or ultrasound to check for gastrointestinal obstruction, cancer, and organ size.
  • Heartworm testing.

Treating vomiting in cats:

Treatment is aimed at finding and treating the underlying cause of the vomiting.

Your veterinarian may wish to correct a fluid and electrolyte imbalance with fluids and feed the cat a low-fat, easily digestible diet. If he is unable to eat a feeding tube may be inserted.

Other treatments may include:

  • Anti-nausea medication to control the vomiting.
  • Antibiotics to treat bacterial infection such as salmonella.
  • Medications and supportive care to treat protozoal infections.
  • Addison’s disease requires life-long administration of the deficient corticosteroids.
  • Pancreatitis – Finding and treating the underlying cause (where possible). Painkillers, anti-nausea medication and supportive care.
  • Surgery to remove any foreign objects your cat may have digested.
  • Surgery to remove tumours and chemotherapy.
  • Hyperthyroidism is usually treated with radioactive iodine which is taken up by the thyroid tumour and destroys it.
  • Liver disease – Supportive care with IV fluids & nutrients, anti-nausea medications (where necessary).
  • Kidney disease is managed with a low protein diet, phosphorous binders, and anti-nausea medication (if necessary).
  • If poisoning is the cause, your veterinarian may pump the stomach, give your cat activated charcoal to absorb some of the toxins, or administer ethanol (for antifreeze poisoning).
  • Supportive care for cats with viral infection while the body fights off the infection.  He may possibly require antibiotics if he develops a secondary bacterial infection.
  • De-worming medications to treat parasitic worms.
  • Eating too fast is an extremely common cause of vomiting in cats and is generally not harmful. Try to feed your cat smaller meals but more frequently.
  • Food allergies or intolerances can be managed by switching to a hypoallergenic diet.

Related articles:

Diarrhea in cats   Constipation in cats   Drooling in cats

Last reviewed 2nd February 2017.

0 replies

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply