A systematic review of Chinese medicinal herbs for acute bronchitis.

OBJECTIVES To assess the effectiveness and safety of Chinese medicinal herbs for treating uncomplicated acute bronchitis. DATA SOURCES We searched the Cochrane Central Register of Controlled Trials (CENTRAL), which includes the Cochrane Acute Respiratory Infections Group's specialized register; The Chinese Cochrane Centre's Controlled Trials Register; MEDLINE; EMBASE; and the Chinese Biomedical Database (CBM). METHODS We only included randomized controlled trials. At least two authors extracted data and assessed trial quality. MAIN RESULTS Four trials reported the time to improvement of cough, fever, and rales associated with bronchitis and showed that patients treated with Chinese herbs had a shorter duration of signs and symptoms. Two trials reported the proportion of patients with improved signs and symptoms at follow-up and showed that Chinese herbs were beneficial in terms of relief of signs and symptoms. Thirteen (13) trials analyzed the data on physician global assessment of improvement at follow-up. Nine (9) of 13 trials showed that Chinese herbs were superior to routine treatment and the other four trials showed a similar effect to routine treatment. In general, Chinese herbs appeared beneficial. Only one trial reported adverse effects during treatment. CONCLUSIONS There are insufficient quality data to recommend the routine use of Chinese herbs for acute bronchitis. The benefit found in this systematic review could be due to publication bias and study-design limitations of the individual studies. In addition, the safety of Chinese herbs is unknown due to the lack of toxicological evidence on these Chinese herbs, though adverse events are rarely reported.