Prokinetics and fundic relaxants in upper functional GI disorders.
Gastrointestinal prokinetics are a heterogeneous class of drugs that stimulate smooth muscle contractions to enhance gastric emptying and intestinal transit. Recently studied prokinetics include antidopaminergic agents (itopride), serotonergic agents (tegaserod and others), and motilin receptor agonists and ghrelin receptor agonists (mitemcinal, TZP101). It has been difficult to establish symptomatic benefit with prokinetic drugs in gastroparesis and functional dyspepsia, because of pathophysiological heterogeneity of the patient populations, a lack of well-accepted endpoints, and inconsistent relationships between changes in motor function and symptomatic outcome. Fundic relaxant drugs are a recent different approach to treatment of gastric motility disorders. Recently studied drugs include drugs under investigation including nitrates, serotonin reuptake blockers, 5-HT(1A) receptor agonists (buspirone and R137696), and muscarinc M1/M2 receptor antagonists (acotiamide or Z-338).