Probiotics for H. pylori infection Original paper

In this randomized controlled trial, supplementation with Lactobacillus reuteri did not improve the infection eradication rate in participants who were also receiving quadruple treatment for Helicobacter pylori infection.

This Study Summary was published on March 1, 2023.


Quadruple therapy with a proton pump inhibitor, bismuth salt, and two antibiotics is a first-line treatment for Helicobacter pylori infection. Helicobacter pylori (H. pylori) is a bacteria that is capable of reducing stomach acid, which leads to gastric microbial overgrowth and higher proportions of other potentially pathogenic microbes. However, treatment often fails and can be accompanied by several side effects.

Although a number of trials have examined the potential beneficial effect of probiotics on H. pylori, including treatment effectiveness and incidence of side effects, the results have been inconsistent.

The study

In this 2-week randomized controlled trial, 421 participants (average age of 53) with H. pylori infection took capsules containing either 100 mg of Lactobacillus reuteri or a placebo. All participants also received quadruple therapy for H. pylori infection.

The primary outcome was the H. pylori eradication rate at 8 weeks after the end of the treatment. The secondary outcome was the incidence of participant-reported adverse effects.

The results

There was no difference between groups in H. pylori eradication rates. The incidence of adverse effects was lower in the probiotic group than in the placebo group.


Because adverse effects were not prespecified as a secondary outcome, we should consider this outcome exploratory.

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This Study Summary was published on March 1, 2023.