Colitis in cats

Colitis is what we call inflammation of the final portion of the intestines. This is very common in cats of all ages and can have many causes. Most cases are mild, but long-term problems can cause severe illness.

Colitis commonly causes diarrhoea and blood in the poo. Many cases are caused by stress or eating things that are hard to digest. These cases usually get better on their own or with a few days of a bland diet. Other causes can be intestinal worms and other infections, food intolerance and allergies, sudden food changes, and inflammatory bowel disease. Repeated episodes of colitis should be investigated.



What is colitis in cats?

Short bouts of colitis are common in cats and usually get better within a couple of days. Stress is a common trigger for colitis in cats. If your cat is not getting better or keeps getting colitis for no obvious reason, another disease may be present.

  • With colitis, the large intestine can’t absorb water anymore due to inflammation, causing watery diarrhoea.
  • Often mucus will be produced.
  • Passing small amounts of blood is also common.
  • Your cat will be very uncomfortable and feel like they need to go immediately. Accidents near the tray or cat flap can happen if they can’t make it in time
  • Often they strain for a little while, even if there is little left to pass.

Speak to a vet if your cat is distressed, appears to be in pain, or if they are passing a lot of blood (more than a teaspoonful per motion).


Symptoms of colitis in cats

  • Soft or watery stools
  • Passing small amounts of stools many times per day
  • Having to go straight away or pooing outside their litter box
  • Straining or pain when pooing
  • Mucus in the stool
  • Lots of gas (flatulence)
  • Small amounts of fresh (bright red) blood in the stool
  • Vomiting



Which cats are at higher risk for colitis?

Colitis is a very common problem and can affect cats of any breed, size and age.

Cats that have a nervous disposition may be more likely to have episodes of colitis induced by stress.

Please speak to a vet if your cat keeps having symptoms of colitis.



Diagnosis of colitis in cats

Sometimes you will know your cat went through something particularly stressful or ate something they shouldn’t. If they are getting better, investigations may not be needed. However, if colitis keeps coming back or is not getting better, your vet may suggest the following:

  • A full physical and rectal examination to check for other signs of disease
  • Faeces tests to check for worms, other intestinal parasites and some bacterial infections
  • Special diets for 4-6 weeks to check for food intolerance and allergies
  • X-rays or ultrasound to check the shape and size of the intestines and surrounding structures
  • Colonoscopy to check the inside of the intestines and take biopsy samples if needed
  • Biopsies to rule out cancer, deep infections and inflammatory conditions


Vet treatment

Veterinary treatment of colitis in cats

Many mild cases of colitis can be treated with home care. See below for more information. More severe or ongoing cases should be investigated and treated according to the cause. This may involve:

  • Special diets, such as hydrolysed diets for food sensitivities or high-fibre diets.
  • Probiotics and prebiotics to improve the intestinal microbiome (gut bacteria)
  • Anti-parasitic medications if intestinal parasites are found
  • Antibiotics if specific infections are present
  • Medications that reduce the activity of the immune system, such as corticosteroids


Home treatment

Home treatment of colitis in cats


Simple cases of colitis respond very well to feeding a simple, easy to digest food for a few days. This should be:

  • Plainly cooked to improve digestibility. Boiling preserves the water content, which helps with fluid losses
  • Low in fat to make digestion easier
  • Low in residue to avoid stimulating the overworked intestine. This means food that is almost completely digested and absorbed
  • Fed in small amounts but frequents meals. This helps with the healing but avoids overstimulating the gut

Plain-boiled chicken or white fish works well for most cats. The easiest way to make sure your cat is getting the right balance of highly digestible ingredients is to buy a prescription veterinary diet, such as Hill’s Prescription Diet I/D. These are:

  • Highly digestible and low in residue
  • Complete in all essential nutrients and supplemented with those that may have been lost due to the diarrhoea
  • Supplemented with the right types of fibre, pre and probiotics to help recovery


  • Probiotics (good gut bacteria) and prebiotics (food for them) are thought to help the gut recover normal function faster.
  • Some types of food-grade clay, such as Kaolin and Montmorillonite, can be used to help firm up the stools and possibly prevent absorption of some toxins produced by bad bacteria.


Living with colitis in cats

  • Any cases of diarrhoea or abnormal stools lasting more than 5-7 days should be assessed by a vet, as an underlying problem is likely.
  • Repeated bouts of colitis without an obvious cause should also be investigated.
  • What a cat eats is the most important thing for managing long-term digestive issues. It is important to work with your vet or vet nurse to find a complete diet that most benefits your cat’s digestion.
  • Probiotic supplements appear to benefit management of chronic colitis in many cats if they are of good quality and appropriate for their problem



Prevention of colitis in cats

Digestive problems are common in cats, but a few things can be done to help prevent them.

  • A healthy, balanced, regular diet will help maintain good gut health.
  • Regular treatment against worms will prevent them from disturbing the gut. Alternatively, regular faeces tests can flag when treatment is necessary.
  • Any food changes should be done gradually, usually around 7 days are needed.
  • If you know a stressful event is coming, some supplements can reduce the risk of colitis developing if used in advance.


When to worry

When to worry about colitis in your cat

Speak to a vet straight away if you notice any of the following in your cat:

  • Passing large amounts of blood in their stool
  • Very lethargic and hiding away.
  • Repeated vomiting
  • Refusing food
  • Showing signs of pain

Joii can help assess if your cat needs a vet visit straight away or can be monitored at home.

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