Hypoglycemia and hyperglycemia can co-exist in the same patient, but usually not at the same point in time. Because hypoglycemia is caused by low blood glucose and hyperglycemia is caused by high blood glucose, it is not possible for a patient to have low blood glucose or high blood glucose at the same time. When a patient has hypoglycemia, if he/she consumes too much sugar it may cause a short-term increase in blood glucose; and when a patient with hyperglycemia overdoses on hypoglycemic medication he/she may have hypoglycemia, so hyperglycemia and hypoglycemia can occur in a single patient. If symptoms of hyperglycemia or hypoglycemia appear you should go to the hospital for examination in time, combine with the actual situation, and take reasonable treatment under the doctor’s guidance, and do not use drugs blindly so as not to miss the opportunity of illness.