Most guidelines on chronic cough emphasize the upper airway cough syndrome (UACS), asthma, and gastro-esophageal reflux disease (GERD) as usual causes of chronic cough in nonsmokers with normal chest radiographs.[6–13] However, the data in these recommendations were reported a long time ago.[3–11] Further, the prevalence of diseases that cause chronic cough, such as asthma, GERD, and other comorbidities, differs according to region and ethnicity. The prevalence of asthma is higher in urbanized communities adopting a Western lifestyle; notably, the prevalence of GERD is reported to be 10% to 20% in the Western area but less than 5% in Asia.