Glucose can be taken before meal if it is to prevent or relieve the symptoms of hypoglycemia, or before or after meal if it is to maintain nutrition, and it is recommended to take it according to the doctor’s instruction. 1. Hypoglycemia: Hypoglycemia usually occurs before meals, often with palpitations, excessive sweating, hunger and other symptoms, you can take glucose to replenish the body’s sugar to relieve the corresponding symptoms. If the starch in the diet can be decomposed to produce glucose very quickly after the meal, there is no need to supplement glucose when there is no hypoglycemia. 2. Nutritional maintenance: If you have a disease that makes it inconvenient for you to eat or eat too little, you need to give glucose to maintain your body’s nutrition, and you can take glucose before or after a meal at this time. Glucose can be taken to relieve hypoglycemia and maintain nutrition. It should be taken as needed, and a doctor can be consulted if necessary.