Sitagliptin is a dipeptidyl peptidase 4 inhibitor, also known as a DPP-4 inhibitor, and can be used alone or in combination with other hypoglycemic agents. The advantages of selegiline are that it is safe, does not cause hypoglycemia, and does not increase body weight. Selegiline can be used in combination with dietary control to improve blood glucose in patients with type 2 diabetes. There are also a few adverse reactions. 5% of patients have gastrointestinal symptoms associated with abdominal pain, diarrhea, nausea, vomiting, etc. Very rarely, adverse reactions include pharyngitis, sore throat, urinary tract infections, and a small number of people will experience elevated white blood cells, alkaline phosphatase, and uric acid.