Efficacy and Safety of Pinaverium Bromide Combined with Flupentixol-melitracen for Diarrhea-type Irritable Bowel Syndrome: A Systematic Review and Meta-analysis

Background: There are many trials on the combination of Pinaverium bromide (PB) and Flupentixol-melitracen (FM) in the treatment of diarrhea-type irritable bowel syndrome (IBS-D), but the sample sizes are small, and the research conclusions are inconsistent. Thus, a meta-analysis was performed, aiming to evaluate the efficacy and safety of this combination therapy in patients with IBS-D.

Methods: A systematic literature search was conducted in 7 databases covering the period up to July 2018 to identify randomized controlled trials (RCTs) of PB combined with FM versus PB alone for IBS-D. The primary outcome was the total symptom relief rate. The other outcomes were the adverse events rate, HAMA/SAS score, and HAMD/SDS score. The methodological quality of the RCTs was assessed independently using 6 criteria according to the Cochrane Collaboration. All data were analyzed using Review Manager 5.3.

Results: Fifteen RCTs with 1487 participants were identified from 2005 to 2018. Compared with PB alone, 15 RCTs showed significant effects of PB plus FM in terms of improved symptom relief in patients with IBS-D (n = 1487, OR = 5.17, 95%CI, 3.79-7.07, P < .00001). Eleven RCTs reported adverse effects in both the PB plus FM and PB groups, there was no statistically significant difference in the adverse events rate between the 2 groups (n = 1207, OR = 2.91, 95%CI, 0.91-9.28, P = 0.07). Two RCTs and 3 RCTs reported HAMA and HAMD scores respectively, and 3 RCTs reported both SAS and SDS scores. After treatment, the above scores in the PB plus FM group were significantly lower than the PB group (all P < .01). However, the trials were deemed to have a medium risk of bias.

Conclusions: The efficacy of PB combined with FM is superior to PB alone in the treatment of IBS-D, and it is safe for clinical use. However, the conclusions still need to be verified by conducting more large-scale and high-quality RCTs.