Inflammatory Bowel Disease in Cats: Signs, Diagnosis and Treatment

By Tailwisp Editorial TeamUpdated October 20, 20264 min read

Occasional vomiting or soft stool is common in cats. Vomiting or diarrhea that goes on for weeks is not, and one possible explanation is inflammatory bowel disease, or IBD. It is one of the most common causes of chronic digestive trouble in middle-aged and older cats, and it needs a careful workup.

What is IBD?

IBD is not one disease but a group of disorders in which inflammatory cells build up in the wall of the stomach, small intestine or colon. The inflamed lining cannot absorb nutrients well and the gut moves abnormally. Depending on the cell type and the part affected, the disease may be called lymphoplasmacytic enteritis, eosinophilic enteritis or colitis. The cause is not fully understood. Theories include an overactive immune response to food proteins or gut bacteria, an altered gut microbiome and genetic factors.

Signs

• Chronic vomiting, perhaps once or twice a week, often dismissed as hairballs. See hairballs in cats.
• Chronic diarrhea, or soft stool.
• Weight loss despite a good, or increased, appetite.
• Reduced appetite and lethargy.
• Excess gas and rumbling.
• Blood or mucus in the stool when the colon is involved.
• A dull coat.

Signs often come and go, which can delay diagnosis. See cat vomiting causes and diarrhea in cats.

IBD versus lymphoma

Small-cell intestinal lymphoma, a slow-growing cancer, can look almost identical to IBD, with the same signs and similar findings on tests. Some experts think the two may be related. Only biopsies, and often additional special tests, can tell them apart, and the treatment differs. See cancer in cats.

How vets diagnose IBD

IBD is a diagnosis of exclusion, so the vet first rules out other causes:

• Fecal tests for parasites and infections. See worms in cats.
• Bloodwork and urine tests, to check for hyperthyroidism, kidney disease, diabetes, liver disease and pancreatitis. See hyperthyroidism in cats, chronic kidney disease in cats and pancreatitis in cats.
• Special blood tests such as B12, folate and a pancreatic test.
• Ultrasound to look at the gut wall thickness and lymph nodes.
• Diet trials, to test for food reactions.
• Biopsies, taken by endoscopy or surgery, to confirm the diagnosis.

Treatment

1. Diet. Many cats improve on a hypoallergenic diet, with a novel protein the cat has not eaten before, or a hydrolyzed protein diet. A trial usually lasts six to eight weeks, with no other foods or treats. See cat food allergies and sensitive stomachs.
2. Medication. If diet is not enough, vets often use steroids such as prednisolone to reduce inflammation, and sometimes other immune-modulating drugs.
3. Vitamin B12. Cats with intestinal disease often have low B12, which is given by injection.
4. Antibiotics or probiotics, in selected cases.
5. Anti-nausea and appetite medications.
6. Treat other conditions found along the way.

Follow your vet's plan, and do not stop medication suddenly.

Living with IBD

• Keep a diary of vomiting, stool and appetite.
• Feed the prescribed diet consistently.
• Avoid treats and table scraps that may trigger flare-ups. See healthy cat treats.
• Attend rechecks, and weigh your cat regularly.
• Keep stress low. See signs of stress in cats.
• Watch for dehydration, and encourage drinking. See how to get a cat to drink more water.

Outlook

Many cats with IBD respond well and enjoy years of good quality life. Some need lifelong medication or diet management. Relapses can occur. Early treatment and consistent follow-up give the best chances.

Giving medications and handling flare-ups

Steroids such as prednisolone are often the backbone of treatment, and the dose is usually reduced gradually once the signs settle. Never stop suddenly. Some cats are given budesonide, which acts more locally in the gut, or other immune-modulating drugs. Side effects may include increased thirst and appetite, so keep fresh water available and watch weight. See how to give a cat liquid medicine and how to give a cat a pill. If a flare-up begins, with vomiting, diarrhea or lost appetite, contact your vet early rather than waiting for a crisis.

Keeping records for your vet

A simple diary helps. Note the date and number of vomiting episodes, stool quality on a scale you choose, appetite, weight and any change in diet or stress. Take photos of unusual stool or vomit. These records help your vet judge whether the plan is working and fine-tune it. Weigh your cat every few weeks, since weight is one of the best measures of how well the gut is absorbing nutrients.

When to see a vet

See a vet if your cat has vomiting or diarrhea for more than a few days, loses weight or stops eating. Use the US vet directory to find a clinic.

This article is general educational information, not veterinary advice. Every cat is different. If your cat is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.