Table 2.

Novel psychotropic agents used for the treatment of irritable bowel syndrome.

Classes of drugs	Mechanism of action	Therapeutic issues
Corticotrophin releasing factor antagonists	Modulation of corticoid system	Limited use, under investigation
Opioidergic agents	Modulation of visceral nociception	Limited central side effects, good efficacy
Cholecystokinin receptor antagonists	Modulation of cholecystokinin pathways	Limited use, under investigation
Somatostatin analogues	Inhibition of rectal sensitivity	Limited use and efficacy, under investigation
Beta-3 adrenergic agonists	Modulation of beta-3 adrenergic system	Limited efficacy in bowel symptoms
N-methyl-D-aspartate antagonists	Central and peripheral analgesics	Limited efficacy, restricted on abdominal pain