A randomised, double blind, placebo-controlled trial set out to evaluate if 28 days of pre-administration with omeprazole (PPI) combined with L. reuteri (Lr) (strains DSM 17938 + ATCC PTA 6475 = Gastrus) may reduce the bacterial load on its own, and increase eradication rate, in H. pylori (Hp)-infected dyspeptic adults. Fifty-five subjects were randomised, whereof 25 completed in the L. reuteri + PPI group and 28 in the placebo + PPI group. Subjects who thereafter still were positive for Hp infection, received a l0-day triple eradication therapy. Follow-up was then conducted at day 90 after initiation of intervention.

Compared to baseline, there was a decline in the proportion of subjects positive for Hp infection one week after cessation of the 28-day supplementation period and at the follow-up at day 90, but with no significant differences between groups. At day 90, compared to baseline, the overall presence and severity of GI symptoms had improved to the same extent in the two groups, measured by GSRS (Gastrointestinal Symptoms Rating Score).

Conclusion: The administration of L. reuteri Gastrus combined with proton pump inhibitor (PPI) did not improve the rate of eradication of H. pylori.