The differences between selegiline and saxagliptin are in terms of drug half-life, dosage used, form of excretion and interacting drugs. Selegiline and saxagliptin both belong to the dipeptidyl peptidase 4 (DPP-4) competitive inhibitors, mainly used in type 2 diabetes mellitus fasting and postprandial glucose control, the difference is as follows: 1. Half-life is different. The half-life of selegiline is more than 12 hours, while the half-life of saxagliptin is only 2.5 hours, but the effect can be maintained for 24 hours, but they are all given once a day. 2. Different dosage. Siglitazar is usually given at a dose of 100mg per day, 50mg per day for those with moderate renal insufficiency (endogenous creatinine clearance of 30-49ml/min), and 25mg per day for those with severe renal insufficiency (endogenous creatinine clearance of less than 30ml/min), while saxagliptin is usually given at a dose of 5mg per day, and is currently not recommended for those with moderate-to-severe hepatic or renal insufficiency. 3. Different excretion forms and interacting drugs. Selegiline is generally excreted in the original form with the bile, and other drugs have little effect, but when combined with digoxin should pay attention to the impact of drug efficacy; saxagliptin by the hepatic CYP metabolism enzyme-mediated metabolism of the excretion of saxagliptin by the corresponding hepatic enzyme inhibitors, such as ketoconazole, itraconazole and other effects, the use of the drug should be appropriate to reduce the amount of. The above drugs should be used under the guidance of a specialist, do not use blindly.