Evidence mapPaperPMID 41453849Full record

SynthesisJournal of psychopharmacology (Oxford, England)2026

The therapeutic readiness of probiotics in major depressive disorder: A systematic review of randomised controlled trials.

Dinyadarshini Johnson, Dinesh Sangarran Ramachandram, Jack Doorly, Gerard Clarke, Kok-Gan Chan, Sivakumar Thurairajasingam, Learn-Han Lee, Vengadesh Letchumanan

Abstract readSystematic Review
In one paragraph

Synthesis in Journal of psychopharmacology (Oxford, England), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
field-weighted citation impact
1 · What the graph read from 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.

2 · The registry

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.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Dinyadarshini JohnsonNovel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia.ORCID 0009-0008-7462-5560
Dinesh Sangarran RamachandramSchool of Pharmacy, Monash University Malaysia, Bandar Sunway, Malaysia.ORCID 0000-0001-5390-7026
Jack DoorlyUCD Intern Network, University College Dublin, Ireland.ORCID 0009-0004-7187-3412
Gerard ClarkeDepartment of Psychiatry and Neurobehavioural Science and APC Microbiome Ireland, University College Cork, Ireland.ORCID 0000-0001-9771-3979
Kok-Gan ChanNovel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia.ORCID 0000-0002-1883-1115
Sivakumar ThurairajasingamClinical School Johor Bahru, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Malaysia.ORCID 0000-0003-0676-5656
Learn-Han LeeNovel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia.ORCID 0000-0002-8589-7456
Vengadesh LetchumananNovel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia.ORCID 0000-0002-2145-6854

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundMajor depressive disorder (MDD) is a globally prevalent psychiatric condition associated with significant morbidity and often suboptimal treatment outcomes. Probiotics have emerged as a promising adjunctive therapy targeting the gut-brain axis in MDD.

aimsThis systematic review aimed to critically evaluate the efficacy of probiotics in the treatment of clinically diagnosed MDD, assess methodological quality and therapeutic readiness, and identify research gaps relevant to clinical application.

methodsA systematic search of MEDLINE, Web of Science, and PubMed was conducted in June 2023 in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Double-blind, placebo-controlled, randomised controlled trials (RCTs) involving adults with MDD were included. Risk of bias was assessed using the Cochrane Risk of Bias tool.

resultsThirteen RCTs involving 437 adults aged 18-75 years with MDD were included. Most trials reported improvements in depressive symptoms, particularly in outpatients with mild-to-moderate MDD treated with multi-strain formulations containing

conclusionsProbiotics appear safe and well-tolerated, with modest adjunctive benefit in MDD, most evident for multi-strain formulations in younger, outpatient populations with mild-to-moderate symptoms, supporting an individualised, context-dependent approach. Future trials should stratify patients, extend intervention durations, and integrate mechanistic endpoints to refine patient-tailored recommendations.

Indexed as

Major Depressive DisorderProbioticsAdultHumansMiddle AgedRandomized Controlled Trials as TopicTreatment Outcomemajor depressive disorderprobioticspsychiatricsystematic reviewtherapeutic

Identifiers

PMID41453849
PMCPMC13283502

What Socratic holds

Textmetadata
LicenceCC BY-NC
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Registered trials

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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 Socratic graph.