Byline: Xuehui Wang, Department of Respiratory Medicine, First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China Department of Graduate, Heilongjiang University of Chinese Medicine, Harbin, China.; Ziting Tian; Fengli Gao; Xia Zhang; Jianqiu Liu; Zhuying Li Abstract BACKGROUND: This study aimed to explore the efficacy and safety of Ping Chuan Ke Li (PCKL) as an adjunctive therapy to oral montelukast compared with placebo plus montelukast for treating patients with chronic asthma (CAS). METHODS: This randomized controlled trial involved 72 patients with CAS. They were randomly allocated to an intervention group or a control group, 36 subjects per group. Participants in the intervention group received PCKL and oral montelukast, while those in the control group received placebo and oral montelukast. The primary outcome was lung function, measured by forced expiratory volume in 1 second (FEV1). The secondary outcomes included quality of life, measured by St. George's Respiratory Questionnaire (SGRQ), and adverse events (AEs). RESULTS: Compared to placebo plus montelukast, PCKL and montelukast revealed greater efficacy in lung function, measured by FEV1 (PÇè CONCLUSION: Traditional Chinese medicine PCKL as an adjunctive therapy to oral montelukast alleviated the symptoms of CAS. Future studies with larger sample sizes are still needed to verify the efficacy and safety of PCKL plus montelukast in patients with CAS.