High fasting blood glucose and low postprandial blood glucose may be the result of irrational use of hypoglycemic drugs, requiring adjustment of hypoglycemic drugs or insulin dosage. For patients with diabetes mellitus, when there is high fasting blood glucose and low postprandial blood glucose, it is usually suggestive of an overdose of postprandial blood glucose medication, which requires a reduction in the dosage of medication to maintain postprandial blood glucose. It is also necessary to pay attention to the occurrence of nocturnal hypoglycemia, if it is nocturnal hypoglycemia, causing reflex fasting blood glucose increase, should reduce the dosage of hypoglycemic drugs, if it is nocturnal hypoglycemia, suggesting that the maintenance of fasting blood glucose drug dosage is insufficient, the need to increase the dosage of hypoglycemic drugs. If fasting blood glucose is high and postprandial blood glucose is low, it is necessary to consult a doctor in time to clarify the cause of this phenomenon, and treat according to the cause to prevent hypoglycemia, which may cause serious consequences.