OBJECTIVE: To assess the effect of Tanreqing injection on airway inflammation in rats. METHODS: A rat model of airway inflammation was generated with lipopolysaccharide (LPS). Tanreqing injection was given by intratracheal instillation, and bronchoalveolar lavage fluid (BALF) from the right lung was collected. BALF total cell and neutrophil counts were then determined. In addition, BALF levels of inflammatory cytokines interleukin-1β, cytokine-induced neutrophil chemoattractant-1, and tumor necrosis factor-α were measured using enzyme linked immunosorbent assay.The middle lobe of the right lung was stained with hematoxylin-eosin and histological changes examined. RESULTS: LPS increased airway inflammation, decreased BALF inflammatory cell count, inflammatory cytokine levels, and suppressed leukocyte influx of the lung. The LPS-induced airway inflammation peaked at 24 h, decreased beginning at 48 h, and had decreased markedly by 96 h. CONCLUSION: Tanreqing injection contains anti-inflammatory properties, and inhibits airway inflammation in a dose-dependent manner. METHODS: A rat model of airway inflammation was generated with lipopolysaccharide (LPS). Tanreqing injection was given by intratracheal instillation, and bronchoalveolar lavage fluid (BALF) from the right lung was collected. BALF levels of inflammatory cytokines interleukin-1β, cytokine-induced neutrophil chemoattractant-1, and tumor necrosis factor-α were measured using enzyme linked immunosorbent assay. The middle lobe of the right lung was stained with hematoxylin-eosin and histological changes examined. RESULTS: LPS increased airway inflammation, decreased BALF inflammatory cell count, inflammatory cytokine levels, and suppressed leukocyte influx of the lung. The LPS-induced airway inflammation peaked at 24 h , decreased initially at 48 h, and had decreased markedly by 96 h. CONCLUSION: Tanreqing injection contains anti-infl ammatory properties, and inhibits airway inflammation in a dose-dependent manner.