Evidence mapPaperPMID 42466639Full record

SynthesisEuropean psychiatry : the journal of the Association of European Psychiatrists2026

Cannabinoid exposure across substance use disorders: Short-term symptom benefits without sustained therapeutic gains in a tier-weighted systematic review.

David Zammit Dimech, Audrey-Ann Zammit Dimech, Louise Grech, Anthony Serracino Inglott

Abstract readSystematic Review
In one paragraph

Synthesis in European psychiatry : the journal of the Association of European Psychiatrists, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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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

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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

4 authors.

David Zammit DimechDivision of Clinical and Surgical Sciences, https://ror.org/01nrxwf90University of Edinburgh, Edinburgh, United Kingdom.ORCID https://orcid.org/0009-0000-6040-2683
Audrey-Ann Zammit DimechDivision of Clinical and Surgical Sciences, https://ror.org/01nrxwf90University of Edinburgh, Edinburgh, United Kingdom.
Louise Grechhttps://ror.org/03a62bv60University of Malta Faculty of Medicine & Surgery, Malta.ORCID https://orcid.org/0000-0002-1644-4680
Anthony Serracino Inglotthttps://ror.org/03a62bv60University of Malta Faculty of Medicine & Surgery, Malta.ORCID https://orcid.org/0000-0003-1196-0376

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundCannabinoids are increasingly discussed as adjuncts in addiction treatment, yet whether they improve clinically meaningful substance use disorder (SUD) outcomes beyond short-term symptom relief is unresolved. We determined whether cannabinoid exposure confers directional efficacy across opioid, alcohol, cocaine, tobacco, and methamphetamine use disorders, distinguishing symptomatic targets from sustained therapeutic outcomes.

methodsPubMed and Embase (1975-2025) were searched for human studies evaluating cannabinoid exposure in relation to SUD outcomes. Two reviewers independently screened and extracted data. Risk of bias was assessed using RoB 2 for randomized controlled trials (RCTs), ROBINS-I for cohort studies, and JBI checklists for cross-sectional, case, and qualitative designs. Six prespecified endpoints (treatment retention, relapse, abstinence, craving, withdrawal severity, consumption) were mapped to each target SUD. Following Synthesis Without Meta-analysis (SWiM) guidance, structured narrative synthesis used a design-based weighting scheme (RCT 1.00 to qualitative 0.25). PROSPERO: CRD420251151193.

resultsNinety-seven studies (41,954 participants) contributed 195 endpoint instances: 89 Beneficial (45.6%), 80 No Significant Effect (41.0%), 12 Mixed/Partial (6.2%), and 14 Harmful/Inferior (7.2%). Short-term symptom targets accounted for most Beneficial findings (76.4%). Sustained outcomes were predominantly No Significant Effect, most pronounced in opioid use disorder. Beneficial symptom findings derived overwhelmingly from weaker study designs (craving 81.5%; withdrawal severity 85.7%; consumption 80.0%).

conclusionsCannabinoids confer short-horizon symptomatic benefits but do not demonstrate efficacy for sustained abstinence, relapse prevention, or retention, most clearly in opioid use disorder, where evidence is strongest. Findings for other disorders remain preliminary. Adequately powered adjunctive randomized trials with biochemically verified endpoints are needed.

Indexed as

CannabinoidsSubstance-Related DisordersHumansCannabinoidscannabinoidsevidence synthesisopioid use disordersubstance use disorderssystematic review

Identifiers

PMID42466639
PMCPMC13420148

What Socratic holds

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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.