Curative Effects of Suhuang Zhike Capsule on Postinfectious Cough: A Meta-Analysis of Randomized Trials

Objective. In this paper, we intended to systematically evaluate the efficacy of Suhuang Zhike Capsule (SZC) on postinfectious cough (PIC) in adults (age > 18). Methods. MEDLINE (PubMed), Chinese National Knowledge Infrastructure (CNKI), Cqvip Database (VIP), and Wanfang Database were researched for the randomized controlled trials (RCTs) of SZC for PIC. The search was limited to human studies, using the search keywords or free-text terms "cough," "post-infectious cough," "postinfectious cough," "post-cold cough," "postviral cough," "postcold cough," "Suhuang Zhike capsule," "Chinese Medicine," and "randomized clinical trials". Two reviewers individually extracted data from the included RCTs and then the extracted data were analyzed using Review Manager 5.3 software. Results. Seven RCTs involving 573 patients entered the inclusion criteria. Findings suggested that, compared with western conventional medicine (WCM) and other Chinese medicine, SZC could effectively improve the efficacy rate (OR 2.68, 95%  CI, 1.48-4.84, P = 0.001; OR 4.86, 95%  CI, 1.50-15.73, P = 0.008, separately). Moreover, SZC could also improve the efficacy rate of Chinese medicine symptom (MD -0.74, 95%  CI, -1.46~-0.02, P = 0.04). However, in terms of cough relief time, more evidence is needed to prove that SZC have an earlier antitussive effect (MD -1.31, 95%  CI, -3.06~0.45, P = 0.14). Conclusion. The current evidence shows that SZC is effective in the treatment of PIC in adults and can significantly improve the effective rate of Chinese medicine symptoms.