Patients with high glucose may have no obvious symptoms or may show symptoms such as excessive drinking and eating; it may cause retinal damage, kidney damage, arteriosclerosis, and other harmful effects. 1.Symptoms (1) There may be no obvious symptoms in the early stage. (2) Systemic symptoms: symptoms such as loss of physical strength, depression, weakness of limbs, etc.; if complicated by infection, symptoms such as low fever, loss of appetite, etc. may occur. (3) Cardiovascular symptoms: including palpitation, arrhythmia, upright hypotension, etc. In severe cases, shock, coma and other manifestations of ketoacidosis may occur. (4) Gastrointestinal symptoms: early hyperphagia, increased food intake and other manifestations, with the development of the disease can be seen in appetite loss, nausea and other manifestations. (5) Urinary symptoms: early polyuria and increased nocturia, and polyuria caused by polydipsia. 2. Hazards (1) Retinal damage: mainly retinal lesions such as microaneurysms, intraretinal hemorrhage, hard exudates, retinal microvascular abnormalities, etc., resulting in acquired blindness, glaucoma, cataract, refractive changes, iridocyclitis and other hazards. (2) Kidney damage: including glomerulosclerosis, glomerulopathy, renal artery lesions, kidney infection and other hazards. (3) Arteriosclerosis: including hazards such as coronary heart disease, ischemic cerebrovascular disease, hypertension, and entrapment aneurysm due to atherosclerosis and arterial calcification. When abnormal blood glucose levels occur, or the above symptoms appear, it is recommended to go to the hospital in time.