Exploring the substitution of cannabis for alcohol and other drugs among a large convenience sample of people who use cannabis.
Chris Wilkins, Jose Romeo, Marta Rychert, Thomas Graydon-Guy
Harm Reduction Journal November 5, 2024 DOI: 10.1186/s12954-024-01111-w (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Cross-sectional survey Peer reviewed |
|---|---|
| Sample size | 23,500 |
| Population | New Zealand respondents who had used cannabis and any of eight other substances in the same six-month period |
| Duration | Six-month period |
| Topics | Cannabis LSD MDMA |
| Keywords | Harm reduction Substance substitution Drug interactions Addiction research Alcohol Cannabis substitution Co-use Methamphetamine Tobacco Public health |
| Citations | 8 |
| Key findings | Cannabis co-use patterns are moderated by age, ethnicity, student status, and urbanicity, with many users reporting reduced use of alcohol and other drugs but increased tobacco use. |
Abstract
The substitution of cannabis for alcohol and other drugs has been conceptualised in a harm reduction framework as where cannabis is used to reduce the negative side-effects, addiction potential, and social stigma of other drugs. There is currently mixed evidence with recent reviews suggesting cannabis co-use patterns may vary by age and ethnicity. Yet few studies have had large enough samples to examine this demographic variation in detail. To explore the co-use of cannabis with alcohol and other drugs within demographic subgroups of a large sample of people who use cannabis. Specifically: (1) whether cannabis is being substituted for other drugs, and (2), whether cannabis use leads to more, less or the same level of other drug use. Online convenience survey promoted via Facebook™ completed by 23,500 New Zealand respondents. Those who had used cannabis and any of eight other substances in the same six-month period were asked if their use of cannabis had any impact on their use of each other substance ("a lot more", "little more", "no impact/same", "little less", "a lot less"). Frequency and quantity used of each other drug was compared by co-use group. Generalised logistic regression models were developed to predict co-use categories. Significant proportions reported cannabis use led to "less" alcohol (60%), synthetic cannabinoid (60%), morphine (44%) and methamphetamine (40%) use. Those who reported using "less" had lower frequency and amount used of other drugs. Approximately seven-out-ten reported cannabis use had "no impact" on LSD, MDMA, and cocaine use. One-in-five reported using cannabis led to "more" tobacco use. Young adults (21-35-years) were more likely to report cannabis use led to "less" drinking and methamphetamine use. Adolescent co-users (16-20 years) reported mixed impacts. Māori were more likely to report cannabis use resulted in "less" alcohol, tobacco, methamphetamine, and LSD use. Students and those living in cities were less likely to report cannabis use lowering use of other substances. Cannabis and other drug co-use patterns are moderated by life stages, lifestyles, cultural perspectives, and urbanicity. Harm reduction initiatives and policy reforms should take account of these moderating factors.
Comparable studies
Other cross-sectional and survey studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Cannabis use before age 15 and subsequent executive functioning 104 chronic cannabis users (49 early-onset before age 15, 55 late-onset after age 15)... | 2011 | Observational cross-sectional study | n = 148 |
| Patterns of simultaneous polysubstance use in drug using university students Drug-using university students | 2006 | Cross-sectional survey | n = 149 |
| Persisting Reductions in Cannabis, Opioid, and Stimulant Misuse After Naturalistic Psychedelic Use: An Online Survey Online survey respondents | 2020 | Cross-sectional survey | |
| User perceptions of the benefits and harms of hallucinogenic drug use: A web-based questionnaire study Users of hallucinogenic drugs who completed a web-based questionnaire | 2010 | Cross-sectional survey | n = 600 |
| Illicit Use of LSD or Psilocybin, but not MDMA or Nonpsychedelic Drugs, is Associated with Mystical Experiences in a Dose-Dependent Manner Adults recruited from the MAPS website and newsletter, most reporting use of various... | 2012 | Cross-sectional survey | n = 337 |
Citations in the library
Cited by 2
- Fusing Specialized Surveys of Rare Populations to Larger Surveys for Generalized Inference: Cross-Sectional Survey Study. Journal of Medical Internet Research April 27, 2026
- Acute Effects of Cannabis on Alcohol Craving and Consumption: A Randomized Controlled Crossover Trial. American Journal of Psychiatry February 1, 2026