Abstract: Objective To clarify the pharmacological effect of Shufeng Jiedu capsules combined with levofloxacin on a multidrug-resistant Pseudomonas aeruginosa infection-induced pneumonia model and death model in mice, and provide data for clinical applications. Methods Experimental animals were randomly divided into six groups according to their body weight: the normal control group, model control group, levofloxacin alone group, and combined-administration groups at three doses (2.08, 1.04, 0.52 g^-1·kg^-1·d^-1) of Shufeng Jiedu capsules combined with levofloxacin. Pneumonia and death models in mice were established via intranasal infection with multidrug-resistant Pseudomonas aeruginosa. Then, the lung indexes, inhibition rate of these indexes, pathological changes of lung tissue, contents of IL-6 and TNF-α in lung tissue, mice mortality, average survival, and life extension rates were detected. Results The three-dose groups of Shufeng Jiedu capsules combined with levofloxacin could significantly reduce the lung indexes, mitigate pathological injury to lung tissue, lower the levels of IL-6 and TNF-α production as well as the mortality of mice, and prolong the average survival. Conclusion The combined administration of Shufeng Jiedu capsules and levofloxacin has a significantly better effect on the mice model of pneumonia and death caused by multidrug-resistant Pseudomonas aeruginosa infection compared with the levofloxacin alone group.

Key words: multidrug-resistant Pseudomonas aeruginosa, pneumonia in mice, Shufeng Jiedu capsules, levofloxacin, combined medication