Twelve-year-old girls who do not have contraindications to insulin and have indications for insulin application can be treated with insulin as prescribed by their physician. Insulin can be used for the treatment of type 1 diabetes, type 2 diabetes with severe infection, surgery or trauma, or type 2 diabetes and diabetic ketoacidosis after diet therapy, oral hypoglycemic drugs are ineffective and other diseases; patients with insulin allergy, hypoglycemia, acute hepatitis and other patients are prohibited from insulin treatment. Therefore, there is no contraindication to the above 12-year-old girl can follow the doctor’s instructions to play insulin therapy; after the use of drugs may appear hypoglycemia, injection site reactions, such as local redness, swelling, hives, itching, etc., the injection site, if not rotating will also cause subcutaneous fat atrophy and hardness of the adverse reactions. Twelve-year-old girls who need to use insulin therapy should be under the guidance of a doctor.