IBD in Dogs (Inflammatory Bowel Disease): Symptoms, Diet and Treatment

IBD vs IBS in Dogs

The two are often confused. IBD involves real inflammation in the gut lining that can be seen on biopsies. IBS (irritable bowel syndrome) has no agreed definition in dogs; it's a diagnosis of exclusion for stress-related bowel upset, usually large-bowel diarrhea, with no inflammation found and no specific test.^9,10 Some dogs with chronic large-bowel diarrhea of unknown cause may have an IBS-like, stress-related bowel disorder, but how it works and how to diagnose it still need more research.^9,11 See colitis in dogs.

Types of Chronic Enteropathy

Vets classify chronic gut disease by what it responds to:¹

• Food-responsive enteropathy: improves with a hydrolyzed or novel-protein diet. This is the most common type.^1,5
• Antibiotic- or microbiome-responsive enteropathy: improves with certain antibiotics; German Shepherds are over-represented.¹
• Immunosuppressant-responsive enteropathy: this is what's usually meant by "true" IBD, and it needs medicines that calm the immune system.¹
• Non-responsive enteropathy: doesn't respond to standard treatment.¹
• Protein-losing enteropathy (PLE): a more serious form in which protein leaks from the gut, causing low blood albumin and sometimes fluid build-up. Yorkshire Terriers and Soft Coated Wheaten Terriers are predisposed.¹

Symptoms of IBD in Dogs

• Chronic or recurring diarrhea, which can be small-bowel (large volumes) or large-bowel (mucus, urgency)^1,12
• Vomiting, sometimes of bile¹
• Poor or picky appetite¹
• Weight loss, poor coat or low energy¹
• Gurgling gut sounds and gas

Signs often come and go. The average age when signs start is about 6 years, but young dogs are often affected; in one study, food-responsive dogs averaged about 3.5 years old.^1,7

How IBD Is Diagnosed

There's no single test. Your vet will first rule out other causes such as parasites, pancreatitis, liver, kidney or hormone disease (including Addison's disease), and cancer, using stool tests, blood tests and imaging.¹ A vitamin B12 (cobalamin) level is commonly checked, since low B12 is frequent and affects treatment.^6,1 Many vets then try a strict diet trial before biopsies. If signs persist or the dog is very ill, biopsies taken by endoscopy or surgery confirm inflammation and rule out cancer.^1,2 Vets often track severity with a scoring system (CCECAI) that covers attitude, appetite, vomiting, stool, weight loss and blood protein.^1,7

Treatment: A Step-by-Step Approach

1. Diet trial. A strict hydrolyzed or novel-protein diet, with no other treats or table food. Most dogs that will respond do so within about 2 weeks, though your vet may continue it longer. If one diet doesn't work, a second diet trial is often worth trying.^1,2
2. B12 supplementation if levels are low, as prescribed by your vet.^1,6
3. Antibiotics or microbiome treatment in selected dogs, used cautiously because of resistance concerns.¹
4. Immune-suppressing medicines such as steroids for dogs that don't respond to diet, often tapered to the lowest effective level over time.^1,13

Many food-responsive dogs do very well long term, and some can later return to a regular diet.^1,7 See food allergies in dogs.

How Long Can a Dog Live With IBD?

Many dogs with IBD do well for years once their disease is controlled, especially food-responsive dogs: in one 3-year study, only 1 of 39 food-responsive dogs died.^7,1 Up to 65% have a good long-term response over 3 years, but 15% to 40% don't respond well to standard treatment in the short term.¹ The outlook is more guarded with low blood protein, low B12, low vitamin D or severe gut changes.^1,14 Protein-losing enteropathy is the most serious form, with a median survival of under 6 months in some reports, though Yorkshire Terriers did much better (a median of 44 months).¹ In a study of 107 dogs with PLE at a referral hospital, about 1 in 5 (21.5%) died in hospital.¹⁵

See diarrhea in dogs and vomiting and diarrhea in dogs.

Frequently Asked Questions

What is IBD in dogs?

Long-term inflammation of the intestines that causes ongoing diarrhea, vomiting, poor appetite or weight loss after other causes are ruled out.

What's the difference between IBD and IBS in dogs?

IBD involves inflammation seen on biopsies. IBS has no agreed definition in dogs and is usually a stress-related diagnosis of exclusion.

What does IBD poop look like in dogs?

It varies: frequent loose or watery stool, sometimes with mucus or blood, often coming and going over weeks.

What is the best food for dogs with IBD?

Usually a hydrolyzed or novel-protein diet chosen with your vet, fed strictly with no other foods.

What should I not feed a dog with IBD?

Avoid treats, table scraps and foods outside the prescribed diet, especially during a diet trial.

What can trigger IBD flare-ups in dogs?

Diet changes or treats, stress, and sometimes infections or skipped medication.

How long can a dog live with IBD?

Many dogs do well for years once the disease is controlled, especially those that respond to diet. Protein-losing forms have a more guarded outlook.

At what age does IBD start in dogs?

On average around 6 years of age, but young dogs are often affected, especially those with food-responsive disease.