Usually, it is considered that if the blood sugar before dinner is higher than the blood sugar 2 hours after lunch by 1.0-2.0mmol/L, the “twilight phenomenon” should be considered. However, there are some patients with “dusk phenomenon” occurring later, showing that the blood sugar before bedtime is higher than the blood sugar 2 hours after dinner. In fact, “dawn phenomenon” and “twilight phenomenon” are two kinds of hyperglycemic phenomena with the same cause but different time. When hyperglycemia occurs at dawn, it is called the “dawn phenomenon” of diabetes, and when it occurs in the evening, it is called the “dusk phenomenon” of diabetes. The mechanism of the two types of hyperglycemia is the same, both are related to the rhythmic secretion of insulin and glucagon (growth hormone, adrenocorticotropic hormone, catecholamines and glucagon) in the body of diabetic patients within 24 hours. Under normal physiological conditions, glucagon secretion starts in the middle of the night and gradually increases, reaching a peak in the early morning and a second peak in the afternoon. In diabetic patients, the “dawn phenomenon” or “twilight phenomenon” of diabetes occurs because the secretion of basal insulin in the body is insufficient and the use of glucose-lowering drugs is not in place, which cannot effectively offset the elevated sugar of glucagon. Once these two phenomena occur in a diabetic patient, it means that the amount of glucose-lowering medication or insulin is insufficient and the treatment plan must be adjusted. The dusk phenomenon is likely to occur in patients with type 1 diabetes; those who are obese and have severe insulin resistance; those with depression, cirrhosis, hyperadrenocorticism and recurrent hypoglycemic reactions; those with radical heart attacks, cerebral hemorrhage and significant stress reactions after major surgery; and those who have subconjunctival dexamethasone injections after diabetic cataract surgery. The following measures are usually taken to deal with the phenomenon of yellowing: 1. Divide lunch into two meals, blood sugar may be controlled. 2.Exercise for 30-60 minutes after lunch. 3. Short-acting insulin before breakfast, Novolin 30R at noon, and short-acting or oral hypoglycemic drugs before dinner are beneficial to control the “twilight phenomenon”. 4, type 1 diabetic patients occur “twilight phenomenon”, the use of insulin pump. 5. Use sulfonylurea glucose-lowering drugs before breakfast and one injection of medium-acting insulin before breakfast. 6.Based on conventional glucose-lowering treatment, use 4-12 mg of cycloheximide before lunch, which is an antihistamine and has the effect of inhibiting growth hormone, with effect in 3-7 days. Bestugastrin (percocet) is a drug for gastric ulcer, which has the effect of inhibiting growth hormone secretion, 50-100 mg before breakfast.