VA Cannabis Research — What Studies Are Underway
The VA currently has six active studies on medical marijuana and has completed ten since 2010. The VA is not ignoring cannabis research — it is conducting it carefully and publishing results regardless of whether they support or complicate the case for cannabis as medicine.
The VA Does Cannabis Research
The VA conducts active cannabis research through the Clinical Science Research and Development service, the Evidence-Based Synthesis Program, and individual medical centers. Results inform policy but do not override the Controlled Substances Act — only the FDA and DEA can do that.
VA San Diego CBD/PTSD Trial — Dr. Marcel Loflin
The VA San Diego CBD/PTSD trial, led by Dr. Marcel Loflin, was the first cannabinoid trial primarily funded by the VA. The study examined CBD as an adjunctive treatment for veterans with PTSD, with a focus on whether CBD could reduce PTSD symptoms when combined with standard evidence-based psychotherapies. The trial represents an important shift in VA research posture — the agency is willing to fund cannabinoid research, even while maintaining its policy restrictions on cannabis recommendations.
VA Evidence-Based Synthesis Program Reviews
The VA Evidence-Based Synthesis Program (ESP) produces comprehensive systematic reviews to inform VA policy and practice. Its review of "Benefits and Harms of Cannabis in Chronic Pain or Post-Traumatic Stress Disorder" has been the foundation document for the VA/DoD Clinical Practice Guideline for PTSD (2023), which ultimately strongly recommends against cannabis for PTSD. This was not a pre-judged conclusion — it is the ESP's honest reading of the evidence base.
This VA ESP-authored review found "low-strength evidence that cannabis alleviates neuropathic pain but insufficient evidence in other pain populations" — notably more conservative than industry-adjacent reviews, because it focused on plant-based cannabis (what veterans actually access) rather than pharmaceutical cannabinoids.
Clinical Science Research and Development (CSR&D) Projects
VA CSR&D funds ongoing projects including neurobiological investigations of cannabis use in veterans, the interaction between cannabis and extinction learning (a core mechanism in PTSD treatment), and the relationship between cannabis use and other substance use disorders common in veterans. These projects are ordinary research funded through ordinary channels — they do not operate under Schedule I research exemptions the way plant cannabis interventional studies must.
The Bonn-Miller/Sisley/MAPS Phase 2 Trial
While not directly VA-funded, the MAPS/Sisley Phase 2 trial of smoked cannabis in veterans with PTSD (Bonn-Miller et al. 2021) represents the most rigorous study of cannabis and veteran PTSD to date. Full discussion of this trial on our PTSD evidence page. It found no statistically significant advantage over placebo on the primary CAPS-5 endpoint, though all groups (including placebo) improved from baseline.
MJP2 — The Next Generation Phase 2
A second MAPS Phase 2 trial (MJP2) received FDA clearance to proceed in November 2024 after three years of partial clinical holds. It targets 320 veterans with moderate-to-severe PTSD, uses cannabis matching commercial potency (addressing the key limitation of the 2021 trial), and employs a parallel (not crossover) design. Funded by a $12.9 million Michigan grant. First participant treatment is projected for early 2026. No results are available as of April 2026.
VA Research Infrastructure Limitations
VA cannabis research — and all U.S. cannabis research — faces structural constraints that decades of Schedule I classification created:
- NIDA monopoly (1968–2021): Research cannabis was sourced exclusively from a University of Mississippi contract until additional DEA licenses were issued in 2021. NIDA-supplied material was typically around half the potency of commercially available products.
- Schedule I bureaucracy: Researchers must coordinate approvals through up to seven regulatory entities with typical approval timelines exceeding 12 months.
- Funding imbalance: As of 2017, only 25% of NIDA cannabinoid funding studied therapeutic properties; the majority funded abuse-focused research.
- Placebo blinding: Cannabis intoxication is obvious to participants, making true double-blinding nearly impossible. In the 2021 MAPS/Sisley trial, 100% of high-THC participants correctly identified receiving active drug.