幼儿的抵抗力较低，容易患感冒、气管炎、肺炎等呼吸道疾病。这些病的一个主要症状就是咳嗽、吐痰。某些家长往往未对孩子的咳嗽情况进行具体分析，就买些止咳药给孩子吃，这对孩子的咳嗽是不利的。咳嗽是人体一种保护性的反射动作，它能使呼吸道的炎症分泌物和异物———... Children’s lower immunity, susceptible to cold, bronchitis, pneumonia and other respiratory diseases. A major symptom of these conditions is coughing and spitting. Some parents often do not make a detailed analysis of the child’s cough, buy some cough medicine for their children to eat, which is harmful to the child’s cough. Cough is a protective reflex action of the human body, it can make respiratory secretions and foreign matter ---.