Probiotics are defined as, "Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host", and have various effects including inhibitory capabilities on pathogens, stimulation of organ functions and activation of immune responses in the human. Probiotics were reported to inhibit Helicobacter pylori not only in vitro, but also in vivo studies. The mechanisms by which probiotics inhibit H. pylori infection include competition for nutrients, production of bactericidal substances, competitive inhibition of adherence and stimulation of host functions and immunity. In addition, probiotics are clinically used for eradication therapy of H. pylori infection, and the effects of probiotics as single treatment and combination use with other drugs including proton pump inhibitors and antibiotics against H. pylori are reported. It has been testified that probiotics increase the eradication rate and prevent adverse events including diarrhea, nausea, vomiting and taste disorder. In the Maastrich V/Florence Consensus Report 2017, it was stated that some probiotics may have a beneficial effect on H. pylori eradication and are effective in reducing side effects of eradication therapy, but more research is needed to answer several questions concerning the mechanisms of probiotics action. In addition, strain specificity, dosages and duration times of probiotics used for H. pylori eradication therapy need to be clarified in future studies.
Keywords: Adverse event; Eradication therapy; H. pylori; Microbiota; Probiotics.