Hypoglycemia will cause a series of clinical symptoms, manifested as sympathetic excitation and central nervous system dysfunction, manifested as hunger, rapid heartbeat, hand tremor, cold sweat, fatigue, unresponsiveness, severe hypoglycemia will appear headache, trance, drowsiness and so on. 1. Normal people with low blood glucose, blood glucose value is generally less than 2.8mmol / L, mostly because of too little diet or exercise caused by how much, a small number of people can have postprandial hypoglycemia. 2. Diabetic patients with low blood glucose, blood glucose value is less than 3.9mmol / L, the reason may be the dose of hypoglycemic drugs is unreasonable, error or delay in meals, drinking alcohol, etc., part of the critically ill patients may not have obvious symptoms in the early stage, will directly appear hypoglycemic coma. Hypoglycemia requires timely supplementation of sugar, including eating sugar cubes, chocolates, cookies, etc. In severe cases, it is necessary to consult a doctor in time and be treated with glucose infusion under the doctor’s guidance.