Typical symptoms: excessive drinking, overeating, excessive urination and weight loss. Excessive drinking is due to the increase of blood sugar in the body, and the increase of osmotic pressure of body fluids will stimulate the thirst center and cause symptoms of excessive drinking. Polyuria is caused by increased drinking water and osmotic diuresis. Eating too much is due to insulin resistance or insulin deficiency, which leads to glucose not being used by cells and insufficient energy supply, thus requiring eating to supplement energy. Losing weight is because glucose in the body can't be converted into energy, which makes the body break down fat and muscles, leading to weight loss.
Atypical symptoms: itchy skin, numbness of limbs, edema of lower limbs, blurred vision, etc. Skin itching is directly related to high glucose toxicity in the body. Numbness of limbs is peripheral neuropathy caused by hyperglycemia. Edema of lower limbs is a complication of renal microvascular disease caused by hyperglycemia, which makes protein lost. Blurred vision is a retinal vascular complication caused by hyperglycemia, which leads to the leakage of lipid blood in blood vessels.
When the patient has the above symptoms, it is necessary to pay attention to check blood sugar.