Synbiotic preparation in men suffering from functional constipation: a randomised controlled trial

BACKGROUND: Evaluating the effects of a commercially available synbiotic preparation (contains both prebiotic and probiotic elements) on functional constipation in males. METHODS: In a randomised controlled trial, a total of 66 adult men with functional constipation were equally allocated to receive a synbiotic mixture or a placebo. The synbiotic mixture or placebo was given as capsules with the same shape and colour, and patients received the capsules twice a day for 4 weeks. RESULTS: A total of 60 patients (31 in the synbiotic group) completed the study. At baseline evaluation, there was no significant difference between the mean stool frequency per week in synbiotic and placebo groups [mean difference of 0.11 times (95% CI: -0.31-0.55), p = 0.58]. However, mean stool frequency increased significantly at weeks 2 [mean difference of 1.32 times (95% CI: 0.21-2.43)] and 4 [mean difference of 1.58 times (95% CI: 0.18-2.99)] in the synbiotic group compared with the placebo group (p = 0.02). A significant difference (p = 0.006) was found at weeks 2 [mean difference of 0.83 (95% CI: 0.20-1.45)] and 4 [mean difference of 0.91 (95% CI: 0.32-1.51)] between the synbiotic and placebo groups regarding the Bristol stool form score. No adverse effect was seen in the synbiotic group. CONCLUSION: The results of this study indicated that this specific commercial product seemed to be effective in increasing stool frequency and improving consistency in this sample of males with functional constipation. However, further studies with longer follow ups, and including females and elderly patients are required to confirm the efficacy of this product for treatment of functional constipation.