Inflammatory Bowel Disease (IBD)

Inflammatory Bowel Disease (IBD)
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What is IBD?

Inflammatory Bowel Disease (IBD) is the collective name for chronic inflammatory conditions of the GI tract.1

While your immune system is supposed to help you fight diseases, it can wrongly attack itself, which causes inflammation. In IBD, your immune system sees any food, bacteria or other things that naturally exist in your intestines as harmful and therefore attack the cells of your GI tract, thinking it will help you when really, it’s only causing harm. This is what causes the varied symptoms of IBD.1-3

What causes IBD?

While the causes of IBD aren’t fully understood, we do know that genes, environmental triggers and the immune system interact to cause the symptoms. We know that genes can change the balance of the immune system, the defensive barrier of the intestine, and the growth of bacteria in it. Intestinal bacteria are a key part of our immune system; we need to know more about what they do, so it’s an important area of research.2

Types of IBD

IBD is sometimes confused with irritable bowel syndrome (IBS) and coeliac disease, but they are different conditions; they just share a few symptoms. IBD is caused by inflammation, but IBS is not. Coeliac disease is caused by an inflammatory reaction to gluten, which can be found in wheat and similar grains, requiring a gluten-free diet.1 Irritable bowel syndrome is a medical diagnosis but may be incorrectly used by some people.

Crohn’s disease and ulcerative colitis are the most common forms of IBD.3

Girls and boys walking in forest
Crohn’s disease

Inflammation can affect any part of the GI tract and can reach through the lining of the bowel wall. It may occur in ‘patches’, affecting some areas but not others.2

Boys and girls gossiping
Ulcerative colitis

The inner lining of the large intestine and rectum can become inflamed, causing ulcers, which may bleed and produce mucus.2,4



Janssen & IBD

At Janssen Ireland, we have always been pioneers in innovative science, finding new and more effective ways to transform the course of immune-mediated diseases like IBD and calm the inner battle waging within patients’ bodies. Today, our pioneering breakthroughs have changed the lives of millions of people with immune-mediated diseases around the world.

We work to restore immune balance with treatments that either engage the brakes or block the accelerators of the immune system. In the future, we aim to use these types of treatment together, and treat anyone’s IBD whether it is mild or severe with the goals of treating it as early as possible, improving patient outcomes, and giving hope to those who have run out of treatment options.


1. Centers for Disease Control and Prevention. What is inflammatory bowel disease (IBD)? Available from: [Accessed October 2023].

2. Crohn’s & Colitis Foundation. The facts about Inflammatory Bowel Diseases. Available from: [Accessed October 2023].

3. Crohn’s & Colitis Foundation. Inflammatory Bowel Disease vs. Irritable Bowel Syndrome. Available from: [Accessed October 2023].

4. Crohn’s & Colitis UK. Ulcerative Colitis. Available at: [Accessed October 2023].