The representative drugs of DPP-4 inhibitors are selegiline, vigliptin, saxagliptin, alogliptin, and liragliptin. DPP-4 inhibitors are a class of drugs for the treatment of type 2 diabetes mellitus, which can inhibit the inactivation of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), increase the levels of endogenous GLP-1 and GIP, promote the release of insulin from pancreatic β-cells, and at the same time inhibit insulin secretion from insulin α-cells, which ultimately serves to lower blood glucose The purpose is to reduce blood glucose. It should be noted that people who are allergic to the components of this class of drugs, type 1 diabetes, diabetic ketoacidosis and other people should not take this type of drug treatment; the use of this class of drugs may be hypoglycemia, rash, dizziness, upper respiratory tract infections and other adverse reactions. Patients who need to use DDP-4 inhibitors for treatment should be under the guidance of a doctor, and should not blindly use the drug on their own.