[New drugs; exenatide and sitagliptin].

Incretin hormones, secreted upon food intake, play an important role in the regulation of blood glucose levels. In type 2 diabetes mellitus, the incretin response is decreased. Substitution of incretin is a novel pharmacological target which restores postprandial glucose homeostasis. Exenatide is a mimetic of the incretin glucagon-like peptide-I (GLP-I). Sitagliptin is an inhibitor of the enzyme dipeptidyl peptidase 4 (DPP-4), which breaks down GLP-I. Both drugs increase the GLP-I concentration, thereby improving insulin secretion from pancreatic p cells, restoring glycaemic control, preventing beta cell destruction, delaying gastric emptying, and reducing food intake.