Irritable Bowel Syndrome: Digestive Disorders

Content provided by the Faculty of the Harvard Medical School

Irritable bowel syndrome

Another common intestinal disorder, associated with a myriad of unpleasant symptoms, is irritable bowel syndrome (IBS). IBS affects millions of people, but has no known cause and no effective remedy. It's probably the number one reason people see gastroenterologists, and accounts for as many as 3.5 million physician visits and 2.2 million prescriptions per year. Today, IBS affects 10%–15% of otherwise healthy adults in North America, with women being twice as likely as men to experience it.

Irritable bowel syndrome may well be the most challenging functional GI disorder for patients and doctors alike. Several studies have found that patients with IBS have a significantly lower quality of life than patients without the syndrome, and that the illness is seriously underdiagnosed. Through the years, IBS has been called by many names — spastic colon, spastic bowel, colitis, mucous colitis, and functional bowel disease. None of the names is quite accurate.

A 2002 survey of 350 people with diagnosed IBS found that 47% reported daily episodes of IBS symptoms and 70% had symptoms more than once a week. Nearly one-fourth said they had symptoms every day of the year. Overall, 43% described their symptoms as severe, 40% said they were moderate, and 17% called them mild.

Unless a person is truly miserable or worried about the possibility of more serious illness, there may be no reason to seek medical attention. In fact, there may be good reason not to; the cost of such care can be high. In rare cases, IBS patients undergo unnecessary surgery. And the drugs used to treat IBS are costly, even though studies have not proved most of them more effective than placebos. On the other hand, studies have shown that IBS patients exhibit a strong placebo effect.

Last updated:	August 21, 2007