Large VA study found cannabis did not substantially reduce opioid use or improve PTSD in veterans
Among 1,413 veterans with opioid use and PTSD, those who also used cannabis showed only marginally fewer opioid use days at baseline, and no differences in opioid use or PTSD symptoms at 4-month follow-up.
Quick Facts
What This Study Found
Of 1,413 veterans with current non-medical opioid use, 30.3% also used cannabis. At baseline, cannabis co-users had slightly fewer opioid use days (small effect, p < .05) and slightly less severe PTSD (d = 0.16, p = .003). At 4-month follow-up, there were no significant differences in substance use or PTSD symptoms between groups.
Key Numbers
1,413 veterans with opioid use; 438 (30.3%) also used cannabis. Baseline: slightly fewer opioid days (small effect) and slightly less PTSD severity (d = 0.16) in cannabis users. Follow-up: no significant differences.
How They Did This
Nationwide longitudinal VA study (1992-2011) of veterans in specialized intensive PTSD treatment. Veterans with opioid use 7+ days/month were compared: those with cannabis co-use vs. those without. Assessed at admission and 4 months post-discharge.
Why This Research Matters
Multiple states have authorized cannabis for PTSD and as an opioid substitute. This large veteran study provides longitudinal evidence that challenges both of these policy rationales.
The Bigger Picture
Despite policy momentum toward authorizing cannabis for PTSD and opioid substitution, this large longitudinal dataset from the veteran population most affected by both conditions does not support substantial benefit.
What This Study Doesn't Tell Us
Observational design; cannabis use was self-reported and not standardized; the population was in intensive PTSD treatment which may overshadow cannabis effects; historical data (1992-2011) may not reflect current cannabis products.
Questions This Raises
- ?Could specific cannabinoid formulations (high-CBD, controlled dosing) produce different results than self-directed cannabis use?
- ?Were the small baseline differences clinically meaningful?
Trust & Context
- Key Stat:
- No significant differences in opioid use or PTSD symptoms at 4-month follow-up
- Evidence Grade:
- Large nationwide longitudinal VA dataset, though observational with self-reported cannabis use.
- Study Age:
- Published in 2020.
- Original Title:
- Impact of cannabis on non-medical opioid use and symptoms of posttraumatic stress disorder: a nationwide longitudinal VA study.
- Published In:
- The American journal of drug and alcohol abuse, 46(6), 812-822 (2020)
- Authors:
- De Aquino, Joao P(12), Sofuoglu, Mehmet(8), Stefanovics, Elina A(2), Rosenheck, Robert A
- Database ID:
- RTHC-02498
Evidence Hierarchy
Follows a group of people over time to track how outcomes develop.
What do these levels mean? →Frequently Asked Questions
Does cannabis help veterans with PTSD?
In this large VA study, veterans who used cannabis alongside opioids showed only tiny baseline differences in PTSD severity compared to those who did not use cannabis, and no differences at follow-up. The authors conclude the data do not encourage cannabis use for either opioid reduction or PTSD treatment.
Can cannabis replace opioids?
This study found no substantial reduction in opioid use among veterans who also used cannabis. At 4-month follow-up, there was no significant difference in substance use patterns between the cannabis co-use and non-cannabis groups.
Read More on RethinkTHC
- anxiety-leaving-house-weed-withdrawal-agoraphobia
- anxiety-response-technique-weed-withdrawal
- anxiety-toolkit-weed-withdrawal
- anxiety-worse-after-quitting-weed
- breathing-exercises-weed-withdrawal-anxiety
- cannabis-induced-anxiety
- does-weed-help-anxiety
- grounding-techniques-weed-withdrawal
- health-anxiety-weed-withdrawal
- manage-anxiety-without-weed
- quitting-weed-anxiety-disorder
- quitting-weed-anxiety-medication-ssri
- self-medicating-anxiety-with-weed
- therapy-quitting-weed-anxiety
- weed-and-anxiety
- weed-biphasic-effect-anxiety
- weed-generalized-anxiety-disorder
- weed-panic-attacks
- weed-paranoia
- weed-social-anxiety
- weed-tolerance-anxiety-stopped-working
- weed-withdrawal-anxiety
- weed-withdrawal-panic-attacks-night
- weed-withdrawal-work-anxiety
- withdrawal-anxiety-vs-real-anxiety
Cite This Study
https://rethinkthc.com/research/RTHC-02498APA
De Aquino, Joao P; Sofuoglu, Mehmet; Stefanovics, Elina A; Rosenheck, Robert A. (2020). Impact of cannabis on non-medical opioid use and symptoms of posttraumatic stress disorder: a nationwide longitudinal VA study.. The American journal of drug and alcohol abuse, 46(6), 812-822. https://doi.org/10.1080/00952990.2020.1818248
MLA
De Aquino, Joao P, et al. "Impact of cannabis on non-medical opioid use and symptoms of posttraumatic stress disorder: a nationwide longitudinal VA study.." The American journal of drug and alcohol abuse, 2020. https://doi.org/10.1080/00952990.2020.1818248
RethinkTHC
RethinkTHC Research Database. "Impact of cannabis on non-medical opioid use and symptoms of..." RTHC-02498. Retrieved from https://rethinkthc.com/research/de-2020-impact-of-cannabis-on
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.