Too high blood glucose can lead to various acute and chronic complications, such as ketoacidosis, diabetic nephropathy, diabetic foot, cardiovascular and cerebrovascular lesions. Too high blood glucose in a short period of time can easily lead to acute complications, such as ketoacidosis, non-ketotic hyperosmolar coma, etc. Patients may experience breathing rotten apple flavor, dizziness, vomiting, coma, etc., and failure to correct the treatment in time may lead to death. Long-term high blood glucose, as the disease progresses, may cause systemic microvascular and macrovascular lesions and peripheral neuropathy, etc. Long-term chronic complications include coronary artery disease, stroke, diabetic nephropathy, diabetic retinopathy, diabetic foot, diabetic skin disease and so on. High blood sugar should be timely medical treatment.