If poor blood glucose control leads to high blood glucose levels for a long time, complications usually occur within about six months. If the blood sugar is well controlled it takes ten years, or even longer, before complications appear. The main complications of diabetes include acute and severe metabolic disorders, infectious diseases, and microvascular lesions. Diabetic patients are prone to have various infections, the most common being kidney infections, which can easily cause patients to have painful urination and require timely treatment. Microangiopathy mainly includes diabetic nephropathy and ophthalmopathy, which attacks between 10-20 years. Patients will experience kidney failure causing oliguria and later will cause diffuse edema in the body. Affecting the blood vessels of the eyes will cause bleeding in the fundus, which requires minimally invasive surgical treatment, but the most important thing is to control blood sugar effectively.