Frontiers in functional dyspepsia.

Functional dyspepsia (FD) refers to unexplained pain or discomfort in the upper abdomen and is commonly seen in gastroenterology practice. The underlying pathophysiologic mechanisms associated with FD are unclear, although traditionally, delayed gastric emptying, visceral hypersensitivity to acid or mechanical distention, and impaired gastric accommodation have been implicated as putative physiologic disturbances. It also remains uncertain whether FD and irritable bowel syndrome are different presentations of the same disorder. Recent data on pathophysiologic mechanisms of FD have focused on postprandial motor disturbances (accelerated gastric emptying, antral-fundic incoordination, and abnormal phasic contractions), alterations of neurohormonal mechanisms in response to a meal, and previous acute infection. Pharmacologic therapies for FD may be guided by these novel mechanisms, as current available therapeutic options are limited. Novel prokinetics and gastric accommodation modulators, visceral analgesics, and agents targeting the neurohormonal response to food ingestion are the next therapeutic frontiers in FD. This review summarizes traditional knowledge and more recent advances in the pathophysiology of FD and potential therapeutic opportunities.