The full name of insulin is insulin injection, which can be given subcutaneously, 15 to 30 minutes before three meals a day, with an additional dose at bedtime if necessary. Type I diabetes mellitus: dosage is 0.5~1 unit/kg; Type II diabetes mellitus: dosage is 0.5~1 unit/kg for sensitive patients, 20 units/kg for general patients, the dosage can be increased appropriately for obese and insulin-insensitive patients. Insulin injection can also be injected intravenously, mainly used in the treatment of diabetic ketoacidosis, hyperglycemic hyperosmolar coma. It can be intravenously dripped into 4-6 units per hour for adults and 0.1 unit/kg per hour for children, and the dose can be adjusted according to the change of blood glucose; it can also be injected for the first time with 10 units plus 4-6 units intramuscularly, and the dose can be adjusted according to the change of blood glucose. In severe cases, 10 units can be injected intravenously first, followed by 4-6 units of intramuscular injection. For severe cases, 10 units can be injected intravenously first, followed by intravenous drip. Allergic reactions may occur after administration, with symptoms such as itching and redness at the injection site, angioneurotic edema, etc.; adverse reactions such as hypoglycemia, palpitations, fatigue, pallor, hunger, weakness, unresponsiveness, vision or hearing abnormalities, impaired consciousness, headache, vertigo, and depression. Contraindicated for those who are allergic to insulin. Patients should use it under the guidance of professional physicians, do not use or stop the drug without authorization.