Introduction: The eradication rate of Helicobacter pylori following the standard triple therapy is declining. This study was conducted to test whether the addition of Lactobacillus reuteri to the standard triple therapy improves the eradication rates as well as the clinical and pathological aspects in H. pylori infection.

Methods: A total of 70 treatment-naïve patients were randomly assigned into group A (the L. reuteri treated group) and group B (the placebo control group). Patients were treated by the standard triple therapy for 2 weeks and either L. reuteri or placebo for 4 weeks. They were examined by symptom questionnaire, H. pylori antigen in stool, upper endoscopy with biopsies for rapid urease test and histopathological examination before treatment and 4 weeks after treatment.

Results: The eradication rate of H. pylori infection was 74.3% and 65.7% for both L. reuteri and placebo treated groups, respectively. There was a significant difference regarding the reported side effects, where patients treated with L. reuteri reported less diarrhea and taste disorders than placebo group. A significant difference within each group was observed after treatment regarding Gastrointestinal Symptom Rating Scale (GSRS) scores; patients treated with L. reuteri showed more improvement of gastrointestinal symptoms than the placebo treated group. The severity and activity of H. pylori associated gastritis were reduced after 4 weeks of therapy in both groups. The L. reuteri treated group showed significant improvement compared with the placebo treated group.

Conclusion: Triple therapy of H. pylori supplemented with L. reuteri increased eradication rate by 8.6%, improved the GSRS score, reduced the reported side effects and improved the histological features of H. pylori infection when compared with placebo-supplemented triple therapy.