Augmented Visceral Perception.

Disorders of augmented visceral perception include functional (or nonulcer) dyspepsia and irritable bowel syndrome (IBS). Enhancement of luminal perception can result from alterations in normal elastic gut wall properties or exaggerated responsiveness of visceral sensory nerve pathways. Standard therapies for functional dyspepsia are effective in subsets of patients and may act in part by compensating for gastric hypersensitivity (as with acid-suppressing drugs) or by enhancing gastric compliance (as with some motor-stimulating agents). Likewise, conventional treatments of patients with IBS reduce visceral perception via effects on sensory nerve function (fiber supplements) or luminal wall properties (antispasmodic drugs). Antidepressants are increasingly used in patients with functional dyspepsia or IBS. These drugs have several purported mechanisms, including 1) luminal relaxation, 2) blunting of visceral hypersensitivity, and 3) modulation of central nervous system pain processing pathways. The efficacy of available and investigational agents that act as visceral analgesics or luminal relaxants is an area of intense pharmaceutical research.