Irritable bowel syndrome (IBS) is a chronic functional disorder of the gastrointestinal tract of unknown etiology. The diagnosis of IBS is made clinically, using symptom-based criteria such as the Manning or Rome criteria. Medical
therapy for this condition has traditionally been directed towards symptom relief, using fiber or
antispasmodic agents. In recent years, emerging data have confirmed the efficacy of
antidepressants, psychological
therapies, 5-HT(3) antagonists, 5-HT(4) agonists, and probiotics in the short-term treatment of IBS, although whether these
therapies influence the long-term course of the disease is unknown. Increasing knowledge regarding the pathophysiological mechanisms underlying IBS has resulted in a number of novel molecular treatments, which show promise. These include
therapies targeting gastrointestinal mucosal
chloride channels and
guanylate cyclase-C receptors, as well as highly selective agents influencing serotonergic transmission that, at the time of writing, do not appear to have any severe deleterious effects. In this article we provide a summary of current and emerging
therapies in this field.