People Who First Used Cannabis to Self-Medicate Consumed More THC and Had Worse Mental Health
Among 3,389 cannabis users, those who first used cannabis for anxiety or depression consumed significantly more THC weekly and had higher paranoia, anxiety, and depression scores than those who started for fun or curiosity.
Quick Facts
What This Study Found
Starting cannabis for anxiety, depression, or because family members used it was associated with higher weekly THC consumption. Self-medication initiation for physical discomfort, pain, anxiety, depression, and psychotic symptoms was linked to higher paranoia scores, with similar patterns for anxiety and depression. Starting for fun or curiosity was associated with lower paranoia and anxiety scores.
Key Numbers
3,389 participants. Mean weekly consumption: 206 THC units (SD=268). Anxiety initiation: +36.22 THC units/week. Depression initiation: +40.37. Family use: +87.43. Fun initiation: -3.71 paranoia points. Curiosity: -2.61 paranoia points. Self-medication initiation linked to higher paranoia, anxiety, depression.
How They Did This
Analysis of the Cannabis&Me population survey (March 2022-July 2024), including 2,573 current and 816 past cannabis users aged 18+. Self-reported reasons for first use, weekly THC unit consumption, and validated measures of paranoia, anxiety, and depressive symptoms.
Why This Research Matters
Asking someone why they first tried cannabis could serve as a simple, cost-effective screening tool to identify those at higher risk for problematic use and mental health symptoms, potentially before problems develop.
The Bigger Picture
This study supports the self-medication hypothesis but with a twist: those who self-medicate from the start appear to develop heavier use patterns and worse mental health outcomes, suggesting the strategy may be counterproductive.
What This Study Doesn't Tell Us
Cross-sectional design cannot establish causation or temporal ordering. Self-reported reasons for first use subject to recall bias. Population survey may underrepresent heavy users. THC units are self-estimated.
Questions This Raises
- ?Can intervening at first cannabis use based on reasons prevent problematic use?
- ?Would screening for self-medication motives improve clinical outcomes?
Trust & Context
- Key Stat:
- Evidence Grade:
- Large sample with THC unit quantification and validated mental health measures, but cross-sectional design limits to moderate.
- Study Age:
- Cannabis&Me survey, March 2022-July 2024.
- Original Title:
- Are reasons for first using cannabis associated with subsequent cannabis consumption (standard THC units) and psychopathology?
- Published In:
- BMJ mental health, 28(1) (2025)
- Authors:
- Spinazzola, Edoardo(11), Degen, Hannah(2), Austin-Zimmerman, Isabelle(10), Trotta, Giulia, Chesney, Edward, Li, Zhikun, Alameda, Luis, Leung, Bok Man, Lang, Yifei, Quattrone, Andrea, Quattrone, Diego, Castrignanò, Erika, Wolff, Kim, Murray, Robin, Freeman, Tom P, Di Forti, Marta
- Database ID:
- RTHC-07709
Evidence Hierarchy
Watches what happens naturally without intervening.
What do these levels mean? →Frequently Asked Questions
Does it matter why you first try cannabis?
Yes. This study found people who first used cannabis to cope with anxiety or depression consumed significantly more THC and had worse mental health outcomes than those who started out of curiosity or for fun.
Could asking about first use help identify at-risk users?
The researchers suggest that asking why someone first used cannabis could be a simple screening tool to identify those at higher risk for heavy use and mental health problems.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-07709APA
Spinazzola, Edoardo; Degen, Hannah; Austin-Zimmerman, Isabelle; Trotta, Giulia; Chesney, Edward; Li, Zhikun; Alameda, Luis; Leung, Bok Man; Lang, Yifei; Quattrone, Andrea; Quattrone, Diego; Castrignanò, Erika; Wolff, Kim; Murray, Robin; Freeman, Tom P; Di Forti, Marta. (2025). Are reasons for first using cannabis associated with subsequent cannabis consumption (standard THC units) and psychopathology?. BMJ mental health, 28(1). https://doi.org/10.1136/bmjment-2025-301810
MLA
Spinazzola, Edoardo, et al. "Are reasons for first using cannabis associated with subsequent cannabis consumption (standard THC units) and psychopathology?." BMJ mental health, 2025. https://doi.org/10.1136/bmjment-2025-301810
RethinkTHC
RethinkTHC Research Database. "Are reasons for first using cannabis associated with subsequ..." RTHC-07709. Retrieved from https://rethinkthc.com/research/spinazzola-2025-are-reasons-for-first
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.