Clinical effectiveness of Chinese patent medicines for functional constipation: insights from a systematic review and Bayesian network-meta-analysis

In recent years, guidelines and consensus statements have recommended Chinese patent medicines (CPMs) for the treatment of functional constipation (FC). The latest Chinese Health Care Directory also lists CPMs for FC; however, the supporting evidence remains insufficient. In this study, we aimed to evaluate the effectiveness and safety of CPMs in the treatment of FC using a network-meta-analysis (NMA).

We searched for eligible randomized controlled trials (RCTs) published in the databases of PubMed, Cochrane Library, Embase, SinoMed, China National Knowledge Infrastructure, Wanfang, and Chinese Scientific Journals Database. Bayesian NMA and pairwise comparisons were performed to determine the frequency of spontaneous bowel movements, clinical effects, recurrence rate, dyschezia score, and defecation time score.

A total of 61 studies were included. The methodological quality of the included studies was relatively poor, and the reliability of the synthetic outcomes was low. Our findings indicate that in older individuals, according to the self-established clinical efficacy criteria, Liuwei Anxiao combined with prokinetics demonstrated superior clinical effectiveness compared to prokinetic monotherapy (risk ratio [RR]: 1.46, 95% confidence interval [CI]: 1.17, 1.96), with lower scores for defecation times (mean difference: −0.30, 95% CI: −0.60, −0.02). Dalitong granules combined with prokinetics showed better clinical efficacy than prokinetic monotherapy (RR: 1.59, 95% CI: 1.03, 2.53). In older participants, based on published clinical efficacy criteria, Shouhui Tongbian capsule combined with an osmotic laxative exhibited superior clinical effectiveness compared to osmotic laxative monotherapy (RR: 1.21, 95% CI: 1.00, 1.48). Reported adverse events included stomachache, diarrhea, and nausea.

Several positive outcomes were observed, including better clinical effects across different criteria and lower defecation frequency scores. However, the quality of the included studies and the conclusions on CPM coverage areas were limited. Future research should include more high-quality studies directly comparing the effects of different CPMs.