Irritable bowel syndrome (IBS) is a disorder of the digestive tract that causes recurring abdominal pain and constipation or diarrhea.
Symptoms vary but often include lower abdominal pain, bloating, gas, and constipation or diarrhea.
A variety of substances and emotional factors can trigger symptoms of IBS.
A doctor usually diagnoses IBS based on the symptoms but does tests to rule out other problems.
Diet modification and drugs can usually relieve specific symptoms.
IBS affects about 10 to 15% of the general population. Some but not all studies suggest women with IBS are more likely to consult a doctor. IBS is the most common disorder diagnosed by gastroenterologists (doctors who specialize in disorders of the digestive tract) and is a common reason why many people visit their primary care physician.
IBS is generally classified as a functional disorder because it impairs the functioning of the body’s normal activities, such as the movement of the intestines, the sensitivity of the nerves of the intestines, or the way in which the brain controls some of these functions. However, although the normal functioning is impaired, there are no structural abnormalities that can be found with an endoscope (a flexible viewing tube), x-rays, biopsies, or blood tests. Thus, IBS is identified by the characteristics of the symptoms and, when done, normal results of tests.