Irritable bowel syndrome

The irritable bowel syndrome (IBS) is a functional gastrointestinal disorde r whose hallmark is abdominal pain or discomfort associated with a change i n the consistency or frequency of stools. In the western world, 8% to 23% o f adults have IBS and its socioeconomic cost is substantial. Research-gener ated insights have led to the understanding of IBS as a disorder of brain-g ut regulation. The experience of symptoms derives from dysregulation of the bidirectional communication system between the gastrointestinal tract and the brain, mediated by neuroendocrine and immunological factors and modulat ed by psychosocial factors. The biopsychosocial model integrates the variou s physical and psychosocial factors that contribute to the patient's illnes s. This model and the recently revised symptom-based criteria(i.e. the "Rom e II criteria") form the basis for establishing a comprehensive and effecti ve approach for the diagnosis and management of the disorder.