Study on Probiotic Impact on PPI-Induced Gut Changes

This study is looking at how the probiotic Lactobacillus rhamnosus GG (found in Culturelle Digestive Probiotic) affects the microbes in your gut when you're taking omeprazole, a medicine like Prilosec that reduces stomach acid. We want to see if Lactobacillus rhamnosus GG can help with changes to your gut microbes that might happen when you take omeprazole. You can join if you are a healthy adult, aged 18 or older, without any current or chronic stomach or bowel symptoms, and you don't follow any special diets. The study will consider itself successful if it finds a change in the variety of gut microbes. The current status of this study is unclear, but it plans to enroll 30 participants.

Study design
This is an interventional study involving 30 healthy participants. It compares omeprazole with either Lactobacillus rhamnosus GG or a placebo (an inactive pill that looks like the study drug).
What's involved
Not specified in the trial record.
Compensation
Not stated in the trial record.
Follow-up
Your gut microbe diversity will be measured at the beginning of the study and again on Day 56.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.

NCT05517928

A Study to Evaluate the Impact of Lactobacillus Rhamnosus GG on Proton Pump Inhibitor-Induced Gut Dysbiosis

Recruiting
NAAges 18+Interventional
Mayo Clinic
~30 participants
Updated 2026-01-08 on ClinicalTrials.gov
What's tested:OmeprazoleLactobacillus rhamnosus GGPlacebo

At a glance

Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Change in Observed Operational Taxonomic Unit (OTU) diversity.
Measured over Baseline, Day 56
Healthy
1 sites across 1 states
Arizona1
  • John DiBaise, MD · PRINCIPAL_INVESTIGATOR · Mayo Clinic

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Eligibility criteria

Inclusion

Individuals on an unrestricted regular diet with no dietary restrictions (vegan, low FODMAP, gluten free, dairy-free etc) or other fad diets (e.g., keto, intermittent fasting, etc.).
Healthy subjects will be screened for current or chronic GI symptoms using a 16-item questionnaire.
Only those with an absence of symptoms will eligible to participate.

Exclusion

For healthy volunteers, will include prior surgery altering the esophagus, stomach, and intestine (except appendectomy).
Chronic daily use of medications affecting GI secretion or motor function.
The presence of any GI-motility affecting systemic diseases or untreated psychiatric disease.
Pregnancy.
  • Change in Observed Operational Taxonomic Unit (OTU) diversity.Baseline, Day 56

    Observed OTU counts in each stool sample will be tested at varying cutoffs by determining the number of OTUs per sample.