Dyspepsia and its overlap with irritable bowel syndrome.

Patients with functional dyspepsia and the irritable bowel syndrome are commonly seen in both primary care and gastroenterology subspecialty settings. Although functional dyspepsia and the irritable bowel syndrome can occur separately, recent research suggests that they often appear together as an overlap syndrome and thus may represent different portions of a unifying spectrum of disease. Despite their widespread prevalence, the pathogenesis of these disorders is not well established but may include impaired gastric emptying, gastric dysrhythmias, hypersensitivity (to acid exposure and to stretch), and Helicobacter pylori infection. Once other disorders in the differential diagnosis have been excluded, treatment of patients with functional dyspepsia, irritable bowel syndrome, and the overlap syndrome without alarm signs underscores current prevailing pathophysiologies and is generally empiric and symptom based. It is hoped that management of these disorders will become more targeted and efficacious as our understanding of them improves.