Published by: Ingrid King. Last Updated on: June 28, 2023 by Crystal Uys


Far too many cat parents accept occasional or even chronic vomiting and diarrhea as a fact of life with cats.  “He just eats too fast.” “She has a sensitive stomach.” “It’s just a hairball.” The truth is that chronic vomiting and/or diarrhea can be an indicator of serious diseases of the small intestine, including inflammatory bowel disease (IBD) and intestinal lymphoma.

What is IBD?

IBD is not a single disease, but rather a group of chronic gastrointestinal disorders caused by inflammation. Inflammatory cells invade the walls of the GI tract, leading to thickening of the walls and disrupting proper GI function. The location of the inflammation can help determine the specific type of IBD. IBD is more common in middle-aged and older cats, but can affect cats at any age.

What causes IBD?

Chronic inflammation of the gastrointestinal tract can be the result of a specific disease, such as a parasitic or bacterial infection. It can also be caused by a food intolerance or food allergy. However, in many cases, it’s impossible to determine the cause of IBD. According to the Cornell Health Center, current theories suggest that these “idiopathic” cases of IBD may be due to a breakdown in the relationship between the normal bacteria that reside in the gastrointestinal tract and the immune system of the GI wall.

Symptoms of IBD

Symptoms most typically include chronic vomiting and diarrhea, but sometimes, constipation can also be a problem. Some cats present with weight loss as the only clinical sign.

Sick and skinny cat sitting on the pavement
Image Credit: turbaliska, Shutterstock

Diagnosis of IBD

To rule out other causes of gastrointestinal problems, your veterinarian will perform diagnostic tests that may include complete blood cell counts, blood chemistry, thyroid function tests, urinalysis, fecal analysis, abdominal x-rays, and ultrasound. The only definitive way to diagnose IBD is through biopsies of small samples of the intestinal lining. Unfortunately, many veterinarians will use endoscopy to obtain these biopsies, which, while less invasive than surgical biopsy, will not always reach the abnormal sections of the intestine.

Medical Treatment

IBD is usually treated with a combination of medical and dietary therapy.  Corticosteroids are used for their anti-inflammatory and immunosuppressant properties, and they can also serve as an appetite stimulant.  However, steroid therapy carries serious longterm side-effects.

The Diet Connection

Since food allergies may play a role in causing IBD, a food elimination trial may be recommended. There are currently two approaches for these trials: a hypoallergenic diet, or a novel protein diet. Hypoallergenic “prescription” diets are made from hydrolyzed proteins, using a conventional protein source like chicken, but the protein is broken down into molecules too small to stimulate the immune system. Novel protein diets must contain a protein that the cat has not previously been exposed to. Unfortunately, with pet food manufacturers coming up with ever more exotic diets, it is becoming increasingly difficult to find a truly novel protein.

Holistically oriented veterinarians have long seen a connection between diet and IBD. These vets believe that commercial pet foods, especially dry foods, are a contributing factor to the large numbers of cats with chronic IBD. They also discovered that many cats improve by simply changing their diets to a balanced grain-free raw meat diet. While results may be achieved with a grain-free canned diet, a raw diet seems to lead to quicker and better results.


The good news is that intestinal disease is very treatable. There is mounting evidence that treating the disease in its early stages will likely prevent a progression to intestinal lymphoma. For most cats, this disease will be chronic, and ongoing monitoring by both cat parents and their veterinarian is critical to successful management.

Happy cat at the veterinarian
Image Credit: 4 PM production, Shutterstock

My personal experience with IBD

My first cat, Feebee, was diagnosed with IBD at around age 12. He was treated with corticosteroids and a high-fiber diet (this was long before I became educated about feline nutrition, and just the thought of it makes me cringe now!) His IBD eventually progressed to intestinal lymphoma, and I elected to do chemotherapy. He did extremely well for another seven months, then he rapidly declined and died at age 15 1/2. I can’t help but wonder, had I known then what I know now about nutrition, whether he would never have developed IBD in the first place.

Featured Image credit: Andriy Blokhin, Shutterstock

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