摘要Cough is a defensive physiological reflex of the human body that enables vital clearance of secretions and harmful elements from the respiratory tract;however,frequent and intense coughing may adversely impact on a patient's work,daily life and social activities.Cough is one of the most commonly observed symptoms in clinical practice arising from a wide range of aetiologies.A chronic cough may be overlooked by clinicians,particularly if reassured by the normal appearance on a chest radiograph.Furthermore,70％-80％ of these patients are readily mislabelled or diagnosed with “chronic bronchitis” or “bronchitis” in China,then typically treated with substantial but ineffective courses of antibiotics,or subjected to repeated investigations as a result of a diagnosis that is unclear,and may thus suffer more discomfort and fimancial burden from their disease.