The Link Between IBS and Fibromyalgia

Irritable bowel syndrome (IBS) and fibromyalgia have a lot in common. Both conditions involve increased sensitivity to pain, can be debilitating and affect more women than men. What's more, research shows that as many as 60 percent of IBS patients also have fibromyalgia and as many as 70 percent of fibromyalgia patients have IBS. That's why leading doctors and scientists are asking: "What's the connection between IBS and fibromyalgia?"

IBS is a disorder that involves abdominal pain and cramping, as well as changes in bowel movements ranging from constipation to diarrhea. 

Fibromyalgia is a common syndrome that involves long-term, body-wide pain and tender points in joints, muscles, tendons, and other soft tissue. 

What They Have in Common

1. Both IBS and Fibromyalgia are categorized as chronic pain disorders caused by changes in the way the central nervous system responds to pain. It's thought that patients with either condition experience heightened pain under conditions where healthy people would feel little to no pain. While IBS pain is described as visceral, manifesting primarily in the stomach and intestines; fibromyalgia pain is described as somatic, manifesting in the skin, muscles and joints.

2. Both conditions are often accompanied by fatigue, anxiety, and depression.

3. Neither condition can be traced back to a specific injury or organic disorder though both frequently start after exposure to extreme stress.

4. Both IBS and fibromyalgia are difficult to diagnose since neither has a specific laboratory or radiologic test that identifies it. Diagnosis is made when a patient identifies a history of symptoms and when other conditions have been ruled out.

5. Both conditions are responsive to similar treatment plans involving medications (antidepressants, anti-anxiety medications and pain medications), exercise, education, cognitive behavioral therapy, counseling, stress reduction and diet modification.

While doctors aren't sure how these conditions are linked, studies on both are leading to better understanding of what might cause them and how to treat them. For example, a study published in the Annals of Rheumatic Disease Journal says that a link between irritable bowel syndrome and fibromyalgia may be related to findings discovered during breath testing. In this study, patients with fibromyalgia or IBS completed a questionnaire and took a specific type of breath test that measured for Small Intestine Bacterial Overgrowth (SIBO). Researchers discovered that abnormal breath test results were more common in patients with fibromyalgia than IBS, but in patients with IBS, the degree of abnormality on breath test was greater in subjects with fibromyalgia.

While studies can't determine yet what causes IBS, fibromyalgia or the connection between the two, scientists and doctors are finding them too interrelated to ignore. That's leading many patients to hope that more studies, better treatments and prevention measures are on the way. 


Annals of Rheumatic Diseases

British Medical Journals

Ann Rheum Dis 2004;63:450-452 doi:10.1136/ard.2003.011502

A link between irritable bowel syndrome and fibromyalgia may be related to findings on lactulose breath testing

M. Pimentel, D. Wallace, D. Hallegua, E. Chow, Y. Kong, S. Park, HC Lin


Medscape Education

Fibromyalgia and Irritable Bowel Syndrome: Is There a Connection?

Afton L. Hassett, PsyD; Daniel J. Clauw, MD