<prompt> Lubiprostone is ?New anticholinergic antidiarrhoealSerotonin agonistNew drug to treat peptic ulcerTo treat irritable bowel syndrome  <response>: Ans. is d i.e., To treat irritable bowel syndrome Lubiprostone is a PG analogue EP4 receptor agonist, developed recently, represents a new strategy in the treatment of constipating-predominant IBS and chronic constipation. It acts by ? Stimulating CI- channel opening in the intestine. Increasing liquid secretion in gut. Decreasing transit time. 