Trial reportPloS one2018
Association of metformin administration with gut microbiome dysbiosis in healthy volunteers.
Trial report in PloS one, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT04089280 (The Effect of Multi-strain Probiotics on Gastrointestinal Symptoms in Patients With Type 2 Diabetes and Metformin Intolerance. A 32-week Prospective, Single Center, Randomized, Placebo Controlled, Cross-over Clinical Trial.), which is not on this map. Cited by 75 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
The Effect of Multi-strain Probiotics on Gastrointestinal Symptoms in Patients With Type 2 Diabetes and Metformin Intolerance. A 32-week Prospective, Single Center, Randomized, Placebo Controlled, Cross-over Clinical Trial.
Who cites it
75 citing papers in PubMed, 2 syntheses or guidelines pooled it, 134 citations in OpenAlex.
- The Effect of Prebiotics and Oral Anti-Diabetic Agents on Gut Microbiome in Patients with Type 2 Diabetes: A Systematic Review and Network Meta-Analysis of Randomised Controlled Trials.Nutrients · 2022 · on this mapPooled it
- Effects of Non-insulin Anti-hyperglycemic Agents on Gut Microbiota: A Systematic Review on Human and Animal Studies.Frontiers in endocrinology · 2020Pooled it
- The effects of prebiotics on gastrointestinal side effects of metformin in youth: A pilot randomized control trial in youth-onset type 2 diabetes.Frontiers in endocrinology · 2023Trial
- Effects of vancomycin-induced gut microbiome alteration on the pharmacodynamics of metformin in healthy male subjects.Clinical and translational science · 2021Trial
- Metformin Affects Gut Microbiome Composition and Function and Circulating Short-Chain Fatty Acids: A Randomized Trial.Diabetes care · 2021Trial
- Metformin-induced changes of the gut microbiota in healthy young men: results of a non-blinded, one-armed intervention study.Diabetologia · 2019Trial
- The eternal struggle between titans: Fecal microbiota transplant (FMT) versus metformin in type 2 diabetes (T2D) gut dysmotility.Journal of advanced research · 2026Review
- The diversity of factors influencing human digestive microbiota in healthy adults and their interaction: a scoping review.BMC nutrition · 2026Article
- Metformin in skin diseases: the role of gut microbiota and immune response.Pharmacological reports : PR · 2026Review
- Gut microbiome disparities reflect type 2 diabetes progression and medication status.iScience · 2026Article
- Mechanistic Links Between the Gut Microbiome and Longevity Therapeutics.Biomedicines · 2026Review
- Rapid and selective gut microbiome modulation by polyherbal formulation in type 2 diabetes.Endocrine connections · 2026Article
- Metformin-Associated Gastrointestinal Intolerance: A Narrative Review of Mechanisms and Clinical Management.Clinical medicine insights. Endocrinology and diabetes · 2026Review
- Microbiotoxicity: an under-recognised player in drug efficacy, toxicity, and health outcomes.npj antimicrobials and resistance · 2025Review
- A Perspective on the Role of Metformin in Treating Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID.ACS pharmacology & translational science · 2025Review
- Gut Feelings: How Microbes, Diet, and Host Immunity Shape Disease.Biomedicines · 2025Review
- Evaluating the Efficacy of Secondary Metabolites in Antibiotic-Induced Dysbiosis: A Narrative Review of Preclinical Studies.Antibiotics (Basel, Switzerland) · 2025Review
- Metformin Effects on SHIP2, AMPKs and Gut Microbiota: Recent Updates on Pharmacology.Current medicinal chemistry · 2025Review
- Metformin-induced changes of the gut microbiota in patients with type 2 diabetes mellitus: results from a prospective cohort study.Endocrine · 2024Article
- Systems Biology of Human Microbiome for the Prediction of Personal Glycaemic Response.Diabetes & metabolism journal · 2024Review
15 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
11 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundMetformin is a widely used first-line drug for treatment of type 2 diabetes. Despite its advantages, metformin has variable therapeutic effects, contraindications, and side effects. Here, for the very first time, we investigate the short-term effect of metformin on the composition of healthy human gut microbiota.
methodsWe used an exploratory longitudinal study design in which the first sample from an individual was the control for further samples. Eighteen healthy individuals were treated with metformin (2 × 850 mg) for 7 days. Stool samples were collected at three time points: prior to administration, 24 hours and 7 days after metformin administration. Taxonomic composition of the gut microbiome was analyzed by massive parallel sequencing of 16S rRNA gene (V3 region).
resultsThere was a significant reduction of inner diversity of gut microbiota observed already 24 hours after metformin administration. We observed an association between the severity of gastrointestinal side effects and the increase in relative abundance of common gut opportunistic pathogen Escherichia-Shigella spp. One week long treatment with metformin was associated with a significant decrease in the families Peptostreptococcaceae and Clostridiaceae_1 and four genera within these families.
conclusionsOur results are in line with previous findings on the capability of metformin to influence gut microbiota. However, for the first time we provide evidence that metformin has an immediate effect on the gut microbiome in humans. It is likely that this effect results from the increase in abundance of opportunistic pathogens and further triggers the occurrence of side effects associated with the observed dysbiosis. An additional randomized controlled trial would be required in order to reach definitive conclusions, as this is an exploratory study without a placebo control arm. Our findings may be further used to create approaches that improve the tolerability of metformin.
Indexed as
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.