The duration of Chinese medicine for a 4-year-old child needs to be determined by the physician according to the condition, and cannot be generalized. Usually, if a child is sick and needs to take Chinese medicine orally, the doctor who sees the child should decide how long to take the medicine according to the specific condition; if it is an emergency, the effect can be seen within a week; if it is a chronic disease, it will take a longer time to treat. If it is a chronic disease, it will take longer. If it is to be taken for a long period of time, it should be consulted weekly, and the physician should formulate a prescription according to the condition of the patient. Meanwhile, it should be noted that during the period of taking Chinese medicine, try to keep the diet as light as possible, you can eat light and warm food, avoid spicy and irritating, raw and cold food. Parents are advised to give their children Chinese medicine under the guidance of a doctor. If taking it for a long period of time, you should consult your doctor weekly to see if the prescription should be changed, and should not blindly take the same herbal prescription for a long period of time on your own.