Patients diagnosed with diabetes mellitus can usually take metformin treatment under the guidance of a doctor, the specific dosage should be based on the specific circumstances of the individual and the drug dosage form. Such as metformin hydrochloride tablets for adults to start once 0.25g, 2-3 times a day, and then according to the efficacy of the gradual increase in dosage, the general daily amount of 1-1.5g, up to a maximum of 2g per day. Metformin belongs to the class of biguanide glucose-lowering drugs, can reduce the intestinal absorption of glucose as well as inhibit the production of glucose in the liver, improve insulin sensitivity, and then play a role in lowering blood sugar. It can be used for the treatment of type 2 diabetes mellitus, which cannot be well controlled by diet control and exercise. It is contraindicated for those who are allergic to this drug, severe renal failure, hepatic insufficiency, acute metabolic acidosis. Adverse reactions such as nausea, vomiting, hypoglycemia, upper respiratory tract infection, dizziness, headache, liver function abnormalities, and skin rash may occur after using the drug. Patients who need to be treated with Metformin should use the drug under the guidance of a doctor.