Irritable bowel syndrome: evaluation and treatment

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder affecting between 10% and 15% of the population of North America. Because physical findings and currently available diagnostic tests lack sufficient specificity for clinical use, the diagnosis of IBS is based on characteristic symptoms including the presence of abdominal pain or discomfort associated with altered bowel function, bloating, and the sensation of incomplete evacuation after bowel movements. Several symptom-based criteria for IBS have been developed to facilitate and standardize its diagnosis. When used in combination with a detailed history, physical examination, and limited diagnostic tests, these criteria are a valid method of diagnosing IBS. Once a confident diagnosis of IBS has been made, treatment of IBS involves reassurance, lifestyle modification, and pharmacologic and psychologic therapy. This article focuses on the clinical evaluation of patients with suspected IBS and treatment options once the syndrome has been diagnosed.