Objective： To assess the effectiveness and safety of an aerosol inhalation of ambroxol in accessory treatment of pneumonia.

Methods： Biomedical databases, including MEDLINE, EMbase, The Cochrane Central Register of Controlled Trials (CENTRAL), CBM-disk and CNKI were searched. Randomized controlled trials (RCTs) and quasi-RCTs that compare aerosol inhalation of ambroxol with placebo or other aerosol inhalation regimens were collected. A critical quality assessment and Meta-analysis were performed for included studies.

Results： Thirteen RCTs were included and all of them were carried out in China. None of the trials described the method of randomization, allocation concealment, blind, and follow-up. With Juni scales, 13 trials scored C degree. Compared with the control group, aerosol inhalation of ambroxol improved total improvement rate and symptoms, and shortened hospital stay. Although statistical difference was not found in some comparisons, all trials showed beneficial tendency. We didn't find any RCTs describing the safety of ambroxol aerosol inhalation.

Conclusion： Because of the low quality of RCTs on ambroxol aerosol inhalation for pneumonia, no reliable conclusion can be drawn from our Meta-analysis. Well-designed RCTs and economic evaluation are urgently needed to evaluate the value and safety of aerosol inhalation of ambroxol in treating pneumonia.