Research study · Addictive Behaviors · 2026
Working memory capacity predicts cannabis-induced effects on alcohol urge
Verified on PubMed Oxford CEBM Level 1B: Randomized Controlled Trial
A 2026 randomized controlled trial in Addictive Behaviors tested dronabinol in short-term memory. The results were mixed. The stronger cannabis cigarette lowered the urge to drink, but mainly in people with average or good scores on a memory test, and the weaker cigarette made no clear difference. This study suggests that a person's ability to.
In plain language
Study overview
This study looked at adults who drink heavily and also use cannabis regularly. Each person came to the lab on three separate days and smoked either a cannabis cigarette with no active ingredient, a weaker cigarette, or a stronger cigarette, and rated how strongly they wanted alcohol before and after.
Findings
The results were mixed. The stronger cannabis cigarette lowered the urge to drink, but mainly in people with average or good scores on a memory test, and the weaker cigarette made no clear difference.
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The deeper readScientific analysis
Background: Cannabis has shown mixed results in its association with alcohol urge, which may be explained by individual differences. One such factor, working memory capacity (WMC) is associated with drug-related cue reactivity and implicated in alcohol use and problems. In the current study, we examined whether WMC moderates the acute effect of cannabis on alcohol urge in a randomized placebo-controlled crossover trial. Methods: Participants aged 21 to 44 (N = 125, 32 % female) reporting heavy alcohol use and cannabis use ≥ twice weekly completed a laboratory protocol across three days where they smoked a placebo, 3.1 % delta-9 tetrahydrocannabinol (THC), and 7.2 % THC cannabis cigarette. Participants were asked to rate their alcohol urge pre and post smoking. Prior to the experimental sessions, participants completed WMC measures including the n-back and the complex span tasks, operation span (OS) and symmetry span (SS). Results: Those with higher WMC, as assessed via the SS task, reported significantly lower alcohol urge after smoking the 7.2 %, but not the 3.1 %, THC dose, relative to placebo. Performance on the OS task was not associated with alcohol urge. Lower WMC as determined via n-back scores was associated with higher alcohol urge overall, but n-back scores did not moderate the impact of cannabis on alcohol urge. Conclusion: Findings suggest individuals with higher but not lower working memory experience lower alcohol urge under acute effects of cannabis. Although cannabis is increasingly perceived as a substitute for alcohol, individuals with lower working memory may be less likely to experience such benefits when attempting to reduce their drinking.
The paper
Citation
Gunn RL, Howe LK, Boyle HK, Metrik J Working memory capacity predicts cannabis-induced effects on alcohol urge. Addictive Behaviors (2026). PubMed 41275744 · DOI
Limitations the authors noted
Laboratory setting may not translate to other settings and populations. Cannabis from the NIDA Drug Supply Program may differ from cannabis currently used by consumers. WMC can fluctuate at the state level and was measured once at baseline. Only acute effects of THC on alcohol urge were measured. Six participants with invalid n-back scores were removed; 13 participants from the parent trial were excluded as they did not complete WMC tasks. Secondary analysis of a parent trial; moderation effect described by authors as modest and in need of replication. Only smoked THC cannabis tested; other cannabinoids and formulations not examined.
In practice
Why this matters
This study suggests that a person's ability to hold and manipulate information may influence whether cannabis reduces their urge to drink alcohol, indicating that such effects are not universal for all heavy drinkers.
Frequently asked questions
Clinical Questions & Answers
What were the primary clinical findings regarding Marijuana smoking and Alcohol consumption?
The results were mixed. The stronger cannabis cigarette lowered the urge to drink, but mainly in people with average or good scores on a memory test, and the weaker cigarette made no clear difference.
What study limitations or clinical safeguards should patients keep in mind?
Laboratory setting may not translate to other settings and populations. Cannabis from the NIDA Drug Supply Program may differ from cannabis currently used by consumers. WMC can fluctuate at the state level and was measured once at baseline.
Browse related research
Condition: Alcohol consumption Condition: Craving Condition: Short-term memory Topic: Marijuana smoking Topic: THC
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Reviewed by Dr. Caplan on October 22, 2026.
This page is general education about a published study. It is not medical advice and does not create a doctor-patient relationship. For care specific to you, book a consultation.
