Effect of Nepeta bracteata Benth. on Chronic Obstructive Pulmonary Disease: A Triple-Blinded, Randomized Clinical Trial

Chronic obstructive pulmonary disease (COPD) imposes a substantial, direct, and indirect economic burden and health complications on healthcare systems. It seems that Persian medicine could facilitate the process of new drug discoveries through reverse pharmacology for the treatment of chronic respiratory diseases. This study aimed to determine the preliminary efficacy of Nepeta bracteata Benth. (N. bracteata) in patients with mild to moderate COPD. In a four-week, triple-blind, randomized, placebo-controlled trial, 78 patients with mild to moderate COPD were randomly allocated to receive either 10 ml syrup of N. bracteata or placebo three times a day, as an add-on to their routine treatment (long-acting beta2-agonist and inhaled corticosteroid). The Spirometry was performed on patients at baseline and end of the intervention to evaluate the effect of the treatment. Forced Expiratory Volume in the first second (FEV1) and FEV1/Forced Vital Capacity (FVC) ratio were considered the primary outcomes. COPD Assessment Test (CAT) was also used for the subjective evaluation of patients’ responses. 64 patients completed the study. The results showed a significant improvement in the CAT score in the N. bracteata group (-9.05) compared to the placebo (-2.78) and control (-2.05) groups (P value = 0.001). The comparison of FEV1 and FEV1/FVC changes showed a significant difference in the N. bracteata group. However, when comparing the three groups, the difference was not statistically significant at the beginning and four weeks after the intervention. It seems that the appropriate response of COPD patients to this drug, especially regarding the quality of life, could make it a choice for complementary therapy in chronic respiratory diseases