In general, glucose is not recommended for diabetic patients, but when patients experience transient hypoglycemia, glucose can be supplemented appropriately according to the situation. When diabetic patients mistakenly infuse a large amount of glucose solution or consume a large amount of sugary drinks due to thirst, or take a large amount of glucose orally, their blood glucose rises rapidly, which makes them prone to acute complications such as diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemia syndrome. DKA is mainly manifested by the aggravation of diabetes mellitus “three more and one less” symptoms (drinking more, eating more, urinating more, weight loss), irritability, drowsiness and other psychiatric symptoms, and in severe cases, there may be dehydration, drop in blood pressure, and impaired consciousness. Hypertonic hyperglycemia syndrome is mainly manifested by the initial symptoms of polydrinking, polyuria and loss of appetite, which gradually evolve into severe dehydration and neuropsychiatric symptoms, with the patient’s slow response, irritability or indifference, drowsiness, and gradual lapse into coma, which is a critical condition with many complications. In general, diabetic patients are recommended to limit the intake of sugar, especially mono- and disaccharide. If diabetic patients experience transient hypoglycemia during medication therapy or during preparation for surgery, glucose supplementation may also be appropriate and should be done under the guidance of a medical professional. Diabetic patients should pay attention to monitoring blood glucose and are advised to seek prompt medical attention if they become unwell.