Sudden cold sweat, weakness and dizziness may be hypoglycemia, and blood sugar should be monitored even. 1. If blood sugar is severely reduced, it may cause hypoglycemic encephalopathy and may even endanger the patient’s life. 2. If the patient’s blood sugar is lower than 3.9 mmol/L, it is generally called hypoglycemia clinically and should be corrected promptly. If conditions are available, hypertonic glucose should be infused intravenously for rapid correction. When there is no condition, you can also take sugar cubes sugar saline or chocolate orally, or you can temporarily eat buns or desserts to correct the disease.3. When hypoglycemia is present, it will generally cause brain hypoxia, and when the cerebellum is hypoxic, patients can have dizziness, nausea, vomiting, balance disorder and ataxia. When the brain is deprived of oxygen, the patient can have blackness in front of the eyes, weakness of the limbs, and symptoms and signs of vegetative nerve function, and the patient mainly shows palpitations, chest tightness, shortness of breath and sweating, etc. 4. Hypoglycemia in diabetic patients is mainly caused by irregular diet during the use of hypoglycemic drugs.