The incidence of type 2 diabetes mellitus is increasing rapidly worldwide together with obesity. This leads to increased demand for new and improved antidiabetic medications which has led to the discovery of the incretin mimetics. The physiological incretins in the body include glucagon like peptide-1 as well as gastric inhibitory polypeptide (also known as glucose-dependent insulinotropic polypeptide), one of their main physiological action is to stimulate glucose dependent insulin secretion. These compounds get deactivated by the dipeptidyl-peptidase IV enzyme. The two classes of drugs that have been developed based on the incretin mechanism include DPP-IV inhibitors and GLP-1 analogues. Both classes of drugs have been found to be beneficial in the treatment of type 2 diabetes mellitus as well as having a relatively good safety profile.