Pharmacology
Tenapanor is a locally acting inhibitor of NHE3 (sodium/hydrogen exchanger 3) expressed on the apical surface of the small intestine and colon; by blocking sodium absorption, it increases luminal water secretion, accelerates intestinal transit, and reduces visceral hypersensitivity-mediated abdominal pain.
Plecanatide is a GC-C agonist and structural analog of human uroguanylin that acts locally on the luminal surface of the intestinal epithelium; activation of GC-C increases intracellular and extracellular cGMP, stimulating chloride and bicarbonate secretion via the CFTR ion channel to increase intestinal fluid and accelerate transit.