Probiotic Supplementation for Treatment of Infection: A Double-Blind Randomized Clinical Trial.

Background/aims: The effects of probiotic supplementation on eradication therapy are not completely understood. In this study, we investigated the effects of continuous probiotic administration on eradication rates, recrudescence, and symptom response following completion of a course of therapy.

Methods: This prospective, randomized, double-blind placebo-controlled trial was performed between June 2018 and 2020. Twohundred seventy patients who received a standard triple regimen for eradication, were included in the study. Participants were randomized to receive a probiotic as adjunctive therapy ( 4.5×10 and Bacillus subtilis 5.0×10; Medilac-S, Hanmi Pharmaceuticals, Seoul, Korea) or a placebo (one tablet thrice daily) for 28 days, following eradication. Participants who showed successful eradication underwent a repeat C-urea breath test after 6 months.

Results: Eradication rates in the probiotic and placebo groups were 77.1% and 72.4%, respectively (=0.48) using per-protocol analysis. Using intention-to-treat analysis, eradication rates were 67.4% and 65.9%, respectively (=0.43). Of 149 patients who were followed-up after 6 months, four patients had recrudescence (2.7%). Recrudescence rates did not differ between the probiotic and placebo groups. Of the 76 patients who had non-ulcer dyspepsia, 60 (78.9%) showed symptom resolution after 6 months. This beneficial effect was most pronounced in patients with postprandial distress syndrome (=0.02).

Conclusions: Consecutive probiotic supplementation following eradication therapy did not increase eradication rates or decrease recrudescence rates.