Many people confuse irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). It’s easy to understand why. Both gastrointestinal (GI) conditions can cause similar uncomfortable symptoms. IBS and IBD are two distinct conditions that require different treatments. Understanding how the two differ can help you find the right symptom relief you need to live a healthier life.

What Is IBS?

IBS is a chronic GI condition that causes changes in your bowel movements. While IBS symptoms may affect your quality of life, this condition does not damage the digestive tract. That means most people don’t experience severe complications from IBS. Experts aren’t sure what causes IBS, but they believe it’s related to hypersensitive nerves in the gut and issues with the ways the brain and gut work together. 

There are three types of IBS:

• IBS with constipation (IBS-C)

• IBS with diarrhea (IBS-D)

• IBS with mixed bowel habits (IBS-M)

Symptoms of IBS include:

• Abdominal pain, often related to bowel movements

• Bloating

• Diarrhea, constipation or both, depending on the type of IBS

• The feeling of an incomplete bowel movement

• Mucus in the stool

What Is IBD?

IBD is a term that refers to two conditions: Crohn’s disease and ulcerative colitis. Unlike IBS, these conditions cause inflammation, which can damage the GI tract. While experts don’t know the exact cause of IBD, it seems to be related to problems with the immune system. In some cases, the immune system may have an incorrect response to a virus or bacteria, leading to inflammation. IBD is also more likely to occur in people with a family history of the disease.

Crohn’s disease can affect any part of the GI tract, most often a portion of the small intestine, while ulcerative colitis occurs in the colon and the rectum. These two conditions share symptoms, including: 

• Abdominal pain

• Bloody stools/rectal bleeding

• Fatigue

• Fevers

• Frequent diarrhea

• Weight loss

Diagnosing and Treating IBS and IBD

If you experience symptoms of IBS or IBD, it’s important to talk to your doctor. They will ask you to describe your symptoms (and estimate how long you’ve been experiencing them) and share information about your diet, medicines you take, and your personal and family health history. Your doctor may be able to diagnose IBS without further testing. But if they suspect you have IBD or another condition, you will likely need to have tests done. These may include:

• A blood test to check for anemia, infection or other GI conditions

• A stool sample to check for blood or signs of other conditions

• Upper endoscopy or colonoscopy to check the digestive tract for signs of inflammation or bleeding

• Imaging, such as contrast radiography, MRI or CT scans

Treatment will depend on the diagnosis. Treatment for IBS usually includes making lifestyle changes, as well as taking medicines in some cases. Your doctor might recommend:

• Eating more fiber, avoiding gluten or following other dietary changes

• Exercising more

• Getting enough sleep

• Reducing stress

• Taking probiotics

Medications for IBS may be prescribed to help control diarrhea and constipation and relieve abdominal pain. Your doctor may also recommend antispasmodics and antidepressants.

For IBD, treatment involves dietary changes and nutrition therapy, as well as medications that may include:

• Anti-inflammatory drugs, such as 5-aminosalicylic acid or corticosteroids

• Immunosuppressive drugs to help prevent the immune system from causing inflammation

• Biologics to block proteins that cause inflammation

• Antibiotics for infections

In more severe cases, surgery to remove damaged areas of the GI tract may be an option. However, early diagnosis and effective management can improve symptoms and, in many cases, bring about disease remission.

Learn more about gastrointestinal and digestive health care at St. Luke’s Health Gastroenterology and Digestive Health.