There are three bowel problems in cats characterized by chronic and protracted diarrhea, sporadic vomiting, malabsorption and, in
long-standing cases, weight loss, anemia, and malnutrition.
Together, these are classified as inflammatory bowel disease
(IBD). Some affected cats show clinical signs in a cyclical pattern, while
others are constantly in discomfort.
All of these diseases are immune-mediated reactions of the
gastrointestinal system to food, bacteria, or parasite antigens. These
reactions get out of control, with large numbers of inflammatory cells
collecting along the gastrointestinal tract and interfering with digestion and
absorption. These syndromes can be managed but are seldom cured, and over the
long term may lead to ulcers or cancer, such as
The following information isn’t intended to replace regular
visits to your veterinarian. If you think your cat may have feline infectious
peritonitis, please see your veterinarian immediately. And remember, please do
not give any medication to your pet without talking to your veterinarian
Other health problems, such as parasites, hyperthyroidism, and kidney disease, must be ruled
out first. Blood work and ultrasound or X-ray studies of the gastrointestinal
tract may be needed.
The role of bacteria in these syndromes has not been clearly
established in cats but has been suggested, since cats tend to have higher
concentrations of bacteria in their small intestines than many other mammals.
This may be related to their being obligate carnivores and having a relatively
short intestinal tract. Some scientists believe that cats fed a
high-protein, low-carbohydrate diet that is more like a wild cat’s natural diet
are less likely to develop these problems.
In each disease in the IBD complex, a different type of
inflammatory cell (plasma cell, eosinophil, lymphocyte, macrophage) accumulates
in the mucous lining of the small or large intestines. Pancreatitis and
intestinal cancer may cause similar signs. A definitive diagnosis is made by
endoscopy or exploratory surgery, during which biopsies are taken of the
Treatment: This is an illness for which the realistic goal is
control, not cure. Treatment tends to be lifelong for most cats. Although the
exact medications may vary for the three versions of IBD, all three types often
respond, at least partially, to dietary changes as described for
lymphocytic-plasmacytic enterocolitis. Along with immunosuppressive drugs such
as prednisolone and azathioprine, omega-3 fatty acids, antioxidants, and
probiotics such as acidophilus may be helpful. Metronidazole, which is used to
lower bacterial counts, can reduce symptoms. Budesonide is a new drug being
looked at for treating IBD. This is a version of a corticosteroid, but it may
have milder side effects. More research must be done before this drug can be
This is the most common inflammatory bowel disease in cats.
Lymphocytes and plasma cells are the predominant inflammatory cells seen on
biopsy of the small and large intestines. The disease has been associated with
giardiasis, food allergy or intolerance, and an overgrowth of intestinal
bacteria. Vomiting is a common sign but is not present in all cases.
Treatment: An antibiotic (metronidazole) is given to treat
bacterial overgrowth and giardiasis. Immunosuppressant drugs such as
azathioprine (Imuran) and/or prednisone are used if other treatments are not
successful. As a general measure, the cat should be placed on a hypoallergenic
diet, either homemade (baby foods or boiled chicken) or commercially obtained
from your veterinarian. The diet should be highly digestible and low in fat. If
colitis is present, fiber may need to be added. A homemade diet may be
developed by consulting a veterinary nutritionist. Raw diets are not
recommended because the cat already has a stressed immune system.