Unstable blood glucose, if there are symptoms such as excessive drinking, dry mouth, etc., may be caused by high blood glucose; if there are frequent symptoms such as dizziness, sweating, panic, etc., may be caused by hypoglycemic reaction; long-term high blood glucose may also cause diabetic nephropathy, fundus hemorrhage and other kinds of diabetes mellitus chronic complications, which will lead to the corresponding clinical symptoms. Symptoms caused by high blood glucose include easy to hunger and overeating, dry mouth, weight loss and other symptoms. Symptoms caused by low blood sugar include panic, excessive sweating, weakness, hunger, anxiety, hand tremor and other symptoms, and in severe cases, hypoglycemic coma can occur. Symptoms of diabetes complications: Unstable long-term blood sugar control can cause diabetic nephropathy, diabetic fundus changes, diabetic peripheral neuropathy and so on. For example, diabetic nephropathy can appear waist acid, positive urine protein, etc.; fundus hemorrhage can appear blurred vision, double vision and other symptoms; diabetic peripheral neuropathy can cause numbness in hands and feet and other symptoms. Patients with unstable blood glucose should take glucose-lowering medication on time under the guidance of a doctor, and review their blood glucose regularly to keep their blood glucose at an ideal level to minimize the occurrence of diabetic complications.