DPP-4 inhibitors are dibrachic peptidase IV inhibitors, an oral hypoglycemic agent used clinically in the treatment of diabetes mellitus. Physiologically, glucose can stimulate the intestinal mucosa to produce enteroglucagon, but enteroglucagon will be rapidly inactivated by the degradation of DPP-4, and usually does not play a particularly strong hypoglycemic effect, while DPP-4 inhibitors can inhibit the activity of DPP-4, so that enteroglucagon can play a longer period of time, and play a hypoglycemic effect. In the clinic, it is mainly used for monotherapy, or combined with other oral hypoglycemic drugs such as metformin, to treat patients with type 2 diabetes that is poorly controlled on the basis of diet and exercise. It should be noted that in pancreatitis or allergy to any component of this class of drugs can not be used, at the same time, according to different liver and kidney conditions to choose the appropriate application of the drug. It is recommended to use the drug under the guidance of a doctor.