Hypoglycemia is a symptom that often occurs in our life, mainly manifested as panic, excessive sweating and dizziness. It is common in diabetic patients and can also occur in normal people when they are excessively hungry. The severity of hypoglycemia symptoms and the degree and speed of blood glucose drop are basically parallel related, but it does not mean that hypoglycemia symptoms will definitely occur when blood glucose drops to a certain value. When the blood sugar drops mildly or in people with repeated hypoglycemia, sometimes there are no symptoms; however, symptoms may also appear if the blood sugar drops too fast. The most common symptom of hypoglycemia is hunger, followed by panic and involuntary trembling of the hands. If the symptoms are not relieved in time, there will be pallor, cold sweat and weakness in the head and whole body. Because the main supply of the brain is glucose, when hypoglycemia occurs, dizziness will appear due to the lack of energy supply to the brain, mental concentration cannot be concentrated, various language and thinking responses will be slowed down, and there may also be mental and behavioral abnormalities. Blood sugar continues to fall, and when blood sugar is lower than 2.8 mmol/L, it is easy to have consciousness disorder or even coma. If hypoglycemia cannot be corrected for a long time, it may lead to hypoglycemic encephalopathy and irreversible coma. Therefore, there may be no symptoms when blood sugar is low, or there may be symptoms, including tremor of hands, panic, sweating, dizziness and other symptoms. Any significant decrease in blood sugar needs to be corrected in time.