44% of medical cannabis patients reported drinking less alcohol after starting cannabis

Among 973 Canadian medical cannabis patients who regularly drank alcohol, 44% reported decreasing their drinking frequency and 8% stopped drinking entirely after starting medical cannabis.

Lucas, Philippe et al.·The International journal on drug policy·2020·Moderate EvidenceCross-Sectional
RTHC-02696Cross SectionalModerate Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

In a survey of 2,102 Canadian medical cannabis patients, 973 who regularly drank alcohol reported that after starting medical cannabis, 44% decreased drinking frequency, 34% reduced drinks per week, and 8% stopped drinking entirely. Being under 55 and having higher baseline alcohol use predicted greater reductions. Intending to use cannabis to reduce alcohol was associated with both reducing and stopping drinking.

Key Numbers

2,102 total respondents; 973 regular alcohol users; 44% decreased frequency; 34% reduced drinks/week; 8% stopped entirely; age <55 and higher baseline use predicted greater reductions.

How They Did This

Cross-sectional survey of 2,102 Canadian medical cannabis program enrollees, analyzing retrospective self-reported changes in alcohol use among the 973 (44%) who reported regular alcohol use before cannabis initiation.

Why This Research Matters

Alcohol causes more health harm than cannabis by most measures. If medical cannabis genuinely reduces alcohol consumption, the net public health effect could be substantially positive.

The Bigger Picture

The substitution hypothesis (cannabis replacing more harmful substances) has significant policy implications. If confirmed by longitudinal studies, cannabis access programs could be framed partly as alcohol reduction interventions.

What This Study Doesn't Tell Us

Retrospective self-report; no control group; participants already enrolled in medical cannabis program (self-selection bias); cannot distinguish substitution from coincidental changes; cross-sectional design.

Questions This Raises

  • ?Would a prospective study with a control group confirm the substitution effect?
  • ?Does the type of medical cannabis condition matter for alcohol substitution?

Trust & Context

Key Stat:
44% reduced alcohol frequency; 8% stopped drinking entirely
Evidence Grade:
Moderate: large sample with detailed outcome measures, but retrospective self-report with no control group.
Study Age:
Published 2020.
Original Title:
Reductions in alcohol use following medical cannabis initiation: results from a large cross-sectional survey of medical cannabis patients in Canada.
Published In:
The International journal on drug policy, 86, 102963 (2020)
Database ID:
RTHC-02696

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Does medical cannabis reduce alcohol use?

In this survey, 44% of regular drinkers reported decreased alcohol frequency after starting medical cannabis, and 8% stopped entirely. However, this was self-reported and retrospective.

Who was most likely to reduce alcohol?

People under 55, those with higher baseline drinking, and those who specifically intended to use cannabis to reduce alcohol had the greatest odds of reducing or stopping.

Read More on RethinkTHC

Cite This Study

RTHC-02696·https://rethinkthc.com/research/RTHC-02696

APA

Lucas, Philippe; Boyd, Susan; Milloy, M-J; Walsh, Zach. (2020). Reductions in alcohol use following medical cannabis initiation: results from a large cross-sectional survey of medical cannabis patients in Canada.. The International journal on drug policy, 86, 102963. https://doi.org/10.1016/j.drugpo.2020.102963

MLA

Lucas, Philippe, et al. "Reductions in alcohol use following medical cannabis initiation: results from a large cross-sectional survey of medical cannabis patients in Canada.." The International journal on drug policy, 2020. https://doi.org/10.1016/j.drugpo.2020.102963

RethinkTHC

RethinkTHC Research Database. "Reductions in alcohol use following medical cannabis initiat..." RTHC-02696. Retrieved from https://rethinkthc.com/research/lucas-2020-reductions-in-alcohol-use

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.