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Inflammatory Bowel Disease

This "catch all"  diagnosis refers to inflammation that occurs anywhere in the intestinal tract. Multiple agents and disorders can cause this inflammation. Certain parasites, such as Giardia,Tritrichomonas and Toxoplasmosis, hookworms and stomach worms, can cause generalized inflammation in the gut.

Many cats with allergic disease develop inflammation in the intestinal tract due to constant stimulation by food proteins and other antigens that their immune systems overreact to.  Rarely, certain fungal infections such as histoplasmosis can become established in the intestines causing chronic inflammation. A major concern for cats with chronic inflammation is that this can progress to a type of cancer called lymphoma.

The only way to definitely diagnose what type of inflammatory bowel disease is present is to obtain biopsies. This requires either surgery or endoscopy under anesthesia. Surgical biopsies are usually preferred because surgery allows a full thickness sample of the intestinal tract to be obtained rather than a small superficial sample of the mucosa alone. In addition, most of the small intestine is not accessible endoscopically, and these locations are the most likely ones to hold lymphoma. Finally, surgery also allows the biopsy of other related organs such as the pancreas and liver that may be involved in the chronic diarrhea.

If biopsies are not able to be obtained due to cost or anesthetic constraints, blood tests such as pancreatic enzyme tests and vitamin B12 and folate levels may be performed looking for signs of intestinal malabsorption.

Treatment- treat the cause whenever possible. Appropriate dewormers for parasitic infections, antibiotics for bacterial infections, antifungals for fungals infections can be highly effective in many cases. Hypoallergenic foods can greatly improve diarrhea in allergic cats. Vitamin B12 and folate supplementation can improve absorption in deficient cats. Pancreatic enzymes can be supplemented in the food. Steroid therapy is often the cornerstone of treatment in cats with inflammatory bowel disease. Anti-inflammatory steroids do have potential side-effects with long term treatment and consequently their use needs to be supervised by your veterinarian.

If lymphoma or other  cancers are present, they are usually treated with chemotherapy or occasionally surgery. The chemotherapy regimens used in cats are generally well tolerated and the cat retains good quality of life and usually lives much longer with treatment.


Cats who are constipated sometimes leave hard stools in different locations throughout the house, usually either close to the box or in out of the way locations. Sometimes they spend time straining to defecate in the box. Occasionally stool gets caught partway through the anus, which is extremely painful. The stool may break off and be dropped in the house. The cat may also seek out cool places such as bath tubs to defecate. Older cats, obese cats and cats with inflammatory bowel disease are more likely to develop constipation.

Mild constipation can be managed with high fiber diets or adding 1-2 tsp canned pumpkin to their diet daily. More significant constipation may require stool softeners such as MiraLax or lactulose. Prescription diets such as Royal Canin Gastro-intestinal Fiber Response Diet have helped many cats with severe constipation. Obese and sedentary cats may benefit from increased exercise and weight loss. Exercise does stimulate intestinal motility in cats as well as people. Sometimes cats become constipated when they are fearful and spend most of their time hidden. Placing a litter box in or close to their hiding place can help increase the frequency of litter box visits and thus reduce stool holding. The longer the stool stays in the colon, the harder it becomes as the  colon removes water from the stool. Some cats may need an enema given by their veterinarian if they are significantly constipated. Do not give human enemas or suppositories to cats- some of them are extremely toxic and potentially fatal if used in cats. Severely constipated cats can develop a megacolon which needs to be treated surgically in most cases. 

Orange Tabby Cat
Grey Kitten


When you gotta go, you gotta go!

A cat with diarrhea who defecates outside the litter box quickly frustrates the most tolerant owner.  Even formed stool passed outside of the litter box is both annoying and a potential health hazard for young children in the household who may come in contact with it.

Diarrhea in cats, just as in people, can cause urgent elimination of stool. Some cats cannot make it to the litter box in time, especially if the litter box is in the basement or some other out of the way location. These cats may be quite painful. Diarrhea may be caused by parasites or other infections, dietary allergies or intolerances, inflammation from inflammatory bowel disease or pancreatitis, and in some cases from cancer.  Litter box accidents can be reduced by placing multiple boxes in easy to access locations. These cats also need to be evaluated medically to determine the cause of their diarrhea.  A fecal sample is needed for parasite analysis. This sample may have to be sent to a reference lab to test for the DNA of difficult to detect bacterial, viral, and parasitic infections.  Sometimes blood samples, X rays, abdominal ultrasound, and even biopsies are needed for definitive diagnosis. Treatment may consist of dietary changes, or short or long term medications. 

Remember that controlling the pain and diarrhea usually is needed to completely resolve the litter box accidents.

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