Patients with high fasting blood glucose should first identify the cause of the elevated blood glucose and then treat the cause. Poor dietary control, not reasonable application of drugs and so on may cause fasting blood sugar rise. If a diabetic patient’s high fasting blood glucose is due to irrational application of medication, the dose of long-acting insulin can be increased under the guidance of the doctor. The onset of action of long-acting insulin is usually in 3-4 hours, and the concentration of the drug in the body is relatively stable after injection, which usually lasts for about 20 hours, and has a better effect on controlling the fasting blood glucose value. If the high fasting blood glucose is caused by insufficient drug dosage and the drug dosage is not adjusted in time. Patients may experience thirst, excessive drinking and urination, fatigue, weight loss, nausea and vomiting, and abdominal discomfort. Therefore, patients are advised to adjust the dose of long-acting insulin under the guidance of a doctor. It should be noted that patients using long-acting insulin are prone to hypoglycemia, so it is recommended to keep watch at all times and always keep cookies, chocolates and other foods available to replenish when hypoglycemia occurs.