OBJECTIVES: For the treatment of chronic cough, conventional treatment involves the administration of medication to treat the cause of the cough. However, due to the insignificant treatment effect and unclear diagnosis methods, East Asian traditional medicine (EATM) has long been used for the treatment of chronic cough. We aimed to investigate the current clinical research status of EATM treatment for chronic cough.

METHODS: The research question was “How much clinical research on EATM treatment has been conducted for chronic cough, and which study design, population, EATM treatment, and outcome measures were used?”. Under the Arksey and O’Malley’s methodological framework, six databases were searched on August 21, 2022. Clinical studies targeting patients with chronic cough regardless of its cause and using EATM treatment were included.

RESULTS: A total of 474 studies were included. The study design was mainly a randomized controlled trial (72.4%). The cause of cough was not reported in most studies (56.1%), and the most frequent cause was upper airway cough syndrome and post-respiratory infection (9.5%, each), followed by mixed causes (7.6%), nonspecific (5.9%), and gastroesophageal reflux disease (4.0%), and the distribution was different according to children and adults. EATM treatment was used for an average of 19.1 days, and herbal medicine alone was the most common (80.6%). In 399 controlled studies, conventional medication was mainly used as a control (81.2%). As for the outcome measure, the total effective rate based on cough symptoms was the most common (94.3%), followed by cough severity (53.8%).

CONCLUSIONS: In future EATM studies on chronic cough, it is necessary to specify the cause of chronic cough or to report that the study was targeting nonspecific chronic cough patients. Furthermore, studies comparing the efficacy of EATM treatment with placebo control should be conducted, and the effect should be evaluated using validated evaluation tools.