咳嗽是呼吸道　的一种防卫反射。当气管内误入异物或分泌物积聚时，便会反射性地出现咳嗽，以便将异物或分泌物排出，使气道通畅，保证呼吸功能正常。不同的呼吸道疾病，其咳嗽声音、出现时间、持续时间以及痰液的性状和全身或局部的症状大都有其本身的特点。因此，做父母的应该认真观察孩子的咳嗽，及时向医生反映病情和咳嗽的特点，以便及早诊断，急取早期治疗。 Cough is a defensive reflex of the respiratory tract. When strayed into the trachea or foreign body secretions, it will reflex cough, in order to discharge foreign body or discharge, the airway patency, to ensure normal respiratory function. Different respiratory diseases, their cough sound, the appearance of time, duration and sputum characteristics and systemic or local symptoms have their own characteristics. Therefore, parents should carefully observe the child’s cough, timely reflect to the doctor’s condition and cough characteristics, in order to early diagnosis and urgent treatment.