The three leading causes of chronic cough in adults are upper airway cough syndrome (UACS, also known as postnasal drip syndrome), asthma, and gastroesophageal reflux disease (GERD).

• 慢性咳嗽的三个主要原因是上呼吸道咳嗽综合症（也称为后鼻道分泌物下滴综合征）、哮喘和胃食管返流疾病。