Omeprazole and gut bacteria in adults with obesity and acid reflux
Tests omeprazole's effect on gut bacteria in adults with obesity and reflux.
Plain-language title generated from the registry record
Registry title: Effect of Omeprazole on Gut Microbiota in Adults With Obesity and GERD
Key facts
- Where
- Moscow, RussiaSee the site
- Phase
- Phase 4
Could this be for you?
Answer for yourself. This is not a decision: only the study team can say whether you can take part.
- Are you between 50 and 65 years old?
Source: NCT07850960, who can take part
Where in Russia
- Federal Research Centre of Nutrition, Biotechnology and Food SafetyMoscow, RussiaNo longer taking part
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Trial details
- Who runs it
- Federal State Budgetary Scientific Institution
- Trial code
- NCT07850960
- Record updated
- 1 October 2026
- Original description
This randomized, open-label, parallel-group study will evaluate the effect of short-term omeprazole therapy on gut and oral microbiota in adults aged 50-65 years with obesity and symptomatic gastroesophageal reflux disease. Participants will be randomized 1:1 to receive omeprazole 20 mg once daily for 14 days plus standard non-pharmacological recommendations for gastroesophageal reflux disease, or standard non-pharmacological recommendations alone. Clinical and laboratory assessments will be performed at baseline and after 14 days. Stool and saliva samples will be collected to assess gut and oral microbiota, and blood samples will be collected for laboratory biomarkers.Read full original descriptionShow less
Effect of Proton Pump Inhibitors on Gut Microbiota Composition in Adults With Obesity and Gastroesophageal Reflux Disease
This randomized, open-label, parallel-group study will evaluate the effect of short-term omeprazole therapy on gut and oral microbiota in adults aged 50-65 years with obesity and symptomatic gastroesophageal reflux disease. Participants will be randomized 1:1 to receive omeprazole 20 mg once daily for 14 days plus standard non-pharmacological recommendations for gastroesophageal reflux disease, or standard non-pharmacological recommendations alone. Clinical and laboratory assessments will be performed at baseline and after 14 days. Stool and saliva samples will be collected to assess gut and oral microbiota, and blood samples will be collected for laboratory biomarkers.
Inclusion: Age 50 to 65 years, inclusive; Obesity, defined as body mass index (BMI) ≥30 kg/m²; Symptomatic gastroesophageal reflux disease with mild or moderate typical symptoms, including heartburn and/or regurgitation; For female participants, postmenopausal status, defined as absence of menstruation for at least 12 months without another apparent cause of amenorrhea; Written informed consent to participate in the study.
Exclusion: Severe or exacerbated GERD, or GERD requiring acid-suppressive therapy or additional diagnostic evaluation; Use of proton pump inhibitors or histamine H2-receptor antagonists within 8 weeks prior to enrollment; Use of systemic antibiotics within 3 months prior to enrollment; Use of probiotic or synbiotic supplements within 8 weeks prior to enrollment; Inflammatory bowel disease, celiac disease, or other severe chronic gastrointestinal disorders that may substantially affect the gut microbiota; History of bariatric surgery or other major gastrointestinal surgery; Acute infectious or inflammatory disease at enrollment; History of myocardial infarction or stroke; Type 2 diabetes mellitus; Chronic heart failure, New York Heart Association functional class III-IV; Chronic kidney disease with estimated glomerular filtration rate <30 mL/min/1.73 m²; Alcohol dependence or other substance use disorder; Severe psychiatric disorder or cognitive impairment that may interfere with providing informed consent or adherence to the study protocol; Known hypersensitivity or contraindications to omeprazole.