Lactobacillus reuteri
Also known as: L. reuteri, Lactobacillus reuteri DSM 17938
Meta-analyses and systematic reviews in the provided abstracts report that L. reuteri DSM 17938 and other L. reuteri strains are associated with reduced crying time in infantile colic in several randomised trials, with larger effects in exclusively breastfed infants. Evidence for benefit in oral peri‑implant mucosal conditions is modest and inconsistent, showing short‑term reductions in bleeding on probing in some trials but limited or negligible clinical benefit overall. Broader probiotic reviews for acute infectious diarrhoea showed heterogeneity and, in low‑bias studies, no clear difference versus control.
Last reviewed: 2026-10-14 · 4 indexed studies
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Overview
Lactobacillus reuteri is a probiotic bacterial species sold as an oral supplement and used in infants and adults. Randomised trials and meta-analyses reported strain-specific benefits for infantile colic and modest, short‑term reductions in bleeding on probing when used as an adjunct in peri‑implant mucosal therapy; findings vary by setting and patient subgroup.
Mechanism & Function
Mechanism of Action
Proposed mechanisms include competitive colonisation, modulation of local mucosal immune responses and production of antimicrobial factors; abstracts describe clinical outcomes rather than mechanistic human data.
Physiological Role
Modulation of local microbial communities and mucosal immune signalling in the gastrointestinal tract and oral cavity.
Primary Pathways
Performance / Health Relevance
Not an ergogenic ingredient. Relevance is primarily for gut and oral health outcomes rather than physical performance.
Evidence Review
Practical Use & Dosage
- Minimum Effective Dose
- Not established in provided abstracts; studies used strain DSM 17938 and other L. reuteri strains with varied dosing not specified in the abstracts.
- Optimal Range
- Not established in provided abstracts.
- Upper / Caution Level
- Not established
- Timing
- Varied by study and population; infant trials typically administered daily.
- Best Format
- Oral probiotic preparations (drops/capsules) containing specified L. reuteri strains.
- Bioavailability
- Probiotic effects are strain dependent; clinical outcomes relate to the specific strains studied (eg DSM 17938 or other L. reuteri strains).
- Absorption Considerations
- Viability is required for typical probiotic effects; formulations should ensure live organisms reach the gut or oral cavity as intended.
Safety & Interactions
Side Effects
- •Generally well tolerated; mild gastrointestinal effects reported in probiotic trials (not specified in provided abstracts).
Contraindications
- Severe immunocompromise (caution with live probiotics)
Drug Interactions
- •May be less effective when taken concurrently with antibiotics; timing separation often used in practice (not specified in abstracts).
Who Should Avoid
- •Severely immunocompromised individuals
- •Patients with central venous catheters (general probiotic precaution)
Monitoring
Monitor for signs of infection in high‑risk patients; otherwise routine use in healthy infants and adults reported without serious adverse events in the provided abstracts.
Frequently Asked Questions
Auto-generated from indexed evidence — dosage, safety, interactions, and more.
When is Lactobacillus reuteri typically used or indicated?
Lactobacillus reuteri is most commonly used for: Infantile colic (oral probiotic for infants), Oral health adjunct (peri‑implant mucositis/ peri‑implantitis adjunct), General gut microbiota modulation. Modulation of local microbial communities and mucosal immune signalling in the gastrointestinal tract and oral cavity.
How does Lactobacillus reuteri work?
Proposed mechanisms include competitive colonisation, modulation of local mucosal immune responses and production of antimicrobial factors; abstracts describe clinical outcomes rather than mechanistic human data.
What is the recommended dose of Lactobacillus reuteri?
The optimal range is Not established in provided abstracts.. with a minimum effective dose of Not established in provided abstracts; studies used strain DSM 17938 and other L. reuteri strains with varied dosing not specified in the abstracts.. Best taken: Varied by study and population; infant trials typically administered daily.. Upper / caution level: Not established.
What are the side effects of Lactobacillus reuteri?
Reported side effects include: Generally well tolerated; mild gastrointestinal effects reported in probiotic trials (not specified in provided abstracts).. Monitoring: Monitor for signs of infection in high‑risk patients; otherwise routine use in healthy infants and adults reported without serious adverse events in the provided abstracts.
Does Lactobacillus reuteri interact with medications?
Known or theoretical interactions: May be less effective when taken concurrently with antibiotics; timing separation often used in practice (not specified in abstracts).. Always check with a clinician before combining with prescription medication.
Who should avoid Lactobacillus reuteri?
Lactobacillus reuteri is generally not recommended for: Severely immunocompromised individuals; Patients with central venous catheters (general probiotic precaution); and Severe immunocompromise (caution with live probiotics).
How strong is the evidence for Lactobacillus reuteri?
Evidence level: Moderate (overall score 59/100), based on 4 indexed studies on SuppIndex.
Research & References (4)
Efficacy of adjunctive measures in the non-surgical treatment of peri-implantitis: A systematic review.
Systematic review of adjunctive non‑surgical treatments for peri‑implantitis included two trials using L. reuteri strains; systemic antimicrobials showed greater PD and BoP reductions, while probiotics produced less marked effects.
Treatment of Peri-implant Mucositis: An AAP/AO Systematic Review and Meta-analysis.
AAP/AO systematic review and meta‑analysis of peri‑implant mucositis treatments noted that certain probiotics, including L. reuteri strains, may modestly reduce BoP in the short term in nonsmoking populations, but adjunctive therapy did not provide a clinically significant benefit overall.
Probiotics for infantile colic: Is there evidence beyond doubt? A meta-analysis and systematic review.
Meta‑analysis of probiotics for infantile colic included multiple trials and reported an average reduction in crying time; subgroup analysis showed a larger reduction with L. reuteri DSM 17938 and in exclusively breastfed infants.
Probiotics to prevent infantile colic.
Cochrane review of probiotics to prevent infantile colic examined RCTs including studies of L. reuteri DSM strains; the review included trials of newborn prophylactic use and concluded evidence was emerging but varied by study.
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Research Overview
Moderate EvidenceCite this ingredient
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Stable URL
https://thesuppindex.com/ingredients/lactobacillus-reuteri
SuppIndex. (2026). Lactobacillus reuteri: Evidence summary, dosage and clinical studies. Retrieved October 16, 2026, from https://thesuppindex.com/ingredients/lactobacillus-reuteri
Based on 4 indexed studies · Evidence level: Moderate.
Goal Ratings
Stack Compatibility
Often used alongside other oral hygiene measures or as adjunct to debridement in dental studies; antibiotics may alter efficacy.