Nabilone and Veteran PTSD: Canadian Evidence Led the Way

In Canada, the use of cannabinoids for therapeutic purposes has been backed by some of the most methodologically sound and clinically relevant research in the world. Among these early efforts, nabilone—a synthetic cannabinoid developed as an analog to THC—showed particularly promising results in the treatment of post-traumatic stress disorder (PTSD), especially for stubborn symptoms like chronic nightmares. Nabilone had been approved by Health Canada since the early 1980s for chemotherapy-induced nausea, but its profile expanded in recent decades as clinicians observed its usefulness in mental health conditions. Unlike smoked or vaporized cannabis, nabilone offered a standardized oral dose and consistent pharmacokinetics, qualities attractive to clinicians in structured care environments such as veterans’ hospitals and trauma centers. In retrospect, nabilone’s success was groundbreaking at the time and would help set the stage for broader research into cannabis-based therapies for veterans.

The Jetly Trial: A Canadian Breakthrough

One of the most important early studies in this space was led by Colonel (Ret.) Dr. Rakesh Jetly, a psychiatrist with Canada’s Department of National Defence. In 2015, Jetly and colleagues conducted a double-blind, placebo-controlled crossover trial focusing on Canadian Forces personnel with treatment-resistant PTSD – particularly those suffering from recurring nightmares. This was the first randomized controlled trial (RCT) of any cannabinoid for a specific PTSD symptom (nightmares) in a military population. The trial’s crossover design meant that each participant received nabilone in one phase and an inactive placebo in another phase, each phase lasting several weeks, allowing for direct within-subject comparisons. The sample was small – ten male participants completed the study – but it provided rigorous evidence from within the Canadian Forces’ own clinical infrastructure, lending the results considerable credibility.

Study Details: Participants started on a low nabilone dose (0.5 mg) which was gradually increased weekly up to a maximum of 3 mg over a seven-week period. In one arm of the trial they received nabilone, and in the other arm they received placebo, with neither the patients nor the researchers knowing which was which until the end. One individual did not complete the second phase, but the majority saw both treatments. The focus was on nightmare frequency and intensity, measured using standard PTSD nightmare scales and clinical assessments.

Key Findings (Jetly et al., 2015):

• Nightmare Reduction: Nabilone significantly reduced the frequency and severity of nightmares compared to placebo. By the end of the nabilone treatment phase, about 70% of participants showed improvement in nightmare symptoms, versus only ~22% during the placebo phase. In fact, 44% of the subjects had no distressing dreams at all during the final week on nabilone – a remarkable outcome for patients who had persistent nightmares before.

• Overall PTSD Symptoms: Participants experienced improvements in overall PTSD symptom scores while on nabilone. A PTSD symptom severity index (focused on recurring distressing dreams) dropped significantly more with nabilone than with placebo (an average reduction of –3.6 points vs. –1.0 point, p = 0.03). Clinical ratings also reflected this benefit – on a standard Clinical Global Impression scale, patients were rated as markedly better on nabilone (average score ~1.9, indicating “much improved”) versus a poorer score ~3.2 on placebo (p = 0.05). Consistently, patients reported better general well-being and sleep continuity when taking nabilone.

• Safety and Tolerability: Notably, no serious adverse events occurred during the trial. Nabilone was generally well-tolerated; reported side effects (such as mild dizziness or dry mouth) were mild and transient, and no participants had to withdraw due to side effects. This safety profile was encouraging to clinicians who were wary of adding new medications to an already vulnerable population.

Jetly’s 2015 study was a landmark moment. It demonstrated in a controlled trial what smaller case series had hinted at – that a cannabinoid could alleviate one of the most tormenting symptoms of PTSD. For the first time, a pharmaceutical cannabinoid had been shown to significantly improve a specific PTSD symptom in a military/veteran group. The fact that this breakthrough came from within the Canadian military’s own research and clinical network only strengthened its impact. Dr. Jetly, himself a veteran, understood the complexities of combat trauma and brought that insight to this research. In retrospective view, the Jetly trial set a crucial precedent: it opened the door for serious scientific inquiry into cannabis-based therapies for PTSD in veterans, at a time when such an idea was met with skepticism elsewhere.

Broader Evidence Among Canadian Veterans

Jetly’s findings did not stand in isolation. In the years that followed, a growing body of Canadian research explored the role of cannabis and cannabinoids in veterans’ mental health. One recent study by Sheehy et al. (2025) analyzed data from over 500 Canadian veterans with PTSD and chronic pain to see how medical cannabis use related to their symptom severity and well-being. Interestingly, this large cross-sectional study found no clear statistical association between cannabis use and lower PTSD symptom scores – in other words, on average, veterans using cannabis (whether nabilone or herbal cannabis) did not show significantly lower PTSD severity than those not using it. However, what emerged strongly from the data was that many veterans perceived real benefits from cannabis despite the lack of a broad statistical effect. In fact, the majority of veterans who used cannabis reported that it benefited their mental health in some way.

These self-reported benefits are important. Veterans in the Sheehy et al. study frequently cited improvements in sleep quality and a reduction in reliance on other prescription medications as advantages of using cannabinoids. Such outcomes are meaningful in a population where standard therapies – like SSRIs (antidepressants) or cognitive-behavioral therapy – often prove insufficient or only partially effective. Many veterans with PTSD also suffer from complex comorbid conditions: chronic pain, disturbed sleep cycles, depression, and anxiety. In these cases, even a modest improvement in sleep or a decrease in nightmare intensity can greatly improve daily functioning and quality of life. Canadian veterans have increasingly turned to medical cannabis in the past decade, supported by federal policies (Veterans Affairs Canada now reimburses veterans for medical cannabis within set limits) and driven by patient experiences. Indeed, since Canada legalized recreational cannabis in 2018, the Veterans Affairs spending on medical cannabis reimbursement ballooned from about $51 million in 2017–2018 to $168 million by 2022–2023, reflecting how many veterans were seeking cannabis as an adjunct treatment.

The mixed findings from larger-scale data (like Sheehy’s study showing no universal PTSD score reduction) alongside strong subjective benefits underscore a key point: cannabinoid therapies may not “cure” PTSD across the board, but they can address specific symptoms (such as nightmares or insomnia) and improve overall well-being for certain individuals. Those self-perceived improvements matter greatly, as they can help veterans engage more effectively with other aspects of rehabilitation. A medication that safely modulates REM sleep (and thus reduces nightmare frequency), calms hyperarousal, and improves sleep continuity is not just treating a symptom in isolation – it is potentially removing barriers that prevent healing. For a veteran who finally sleeps through the night without terrors, the next day’s therapy session or work opportunity might become more manageable. In this way, nabilone and related cannabinoids have served as gateway tools to broader recovery, helping some veterans reclaim parts of their lives that chronic PTSD had shut down.

From Nabilone to Broader Cannabis Research

Nabilone’s early success in Canada had ripple effects that extended far beyond the specific use of this one drug. At the time, it provided a proof-of-concept that a THC-based treatment could be rigorously tested, deemed safe, and accepted by regulators for a mental health indication. This was hugely significant in an era when cannabis research elsewhere faced legal and cultural barriers. Because nabilone is a fully legal, pharmaceutically produced cannabinoid, it could be deployed in clinical trials and veteran care pathways that demanded pharmaceutical-grade consistency. In the mid-2010s, herbal cannabis was still viewed with suspicion in many medical circles, but nabilone offered a bridge between the world of cannabis and the world of conventional medicine.

For Canadian researchers and healthcare providers, nabilone became a case study in how a controlled oral THC analog could succeed where unregulated herbal cannabis could not at the time – in formal clinical trials and even in international medical channels. Unlike in the United States (where cannabis remained federally illegal and thus largely off-limits for the VA or for export), Canadian institutions operated within a supportive regulatory framework. This meant that promising findings like Jetly’s could be translated into practice relatively quickly, and Canadian companies could even explore exporting THC-based medicines to other countries that allowed it. Nabilone’s regulatory acceptance and the Canadian government’s openness to cannabinoid therapy thus positioned Canada as a leader. It wasn’t just about one medication; it was about pioneering a new therapeutic domain.

Crucially, the pioneering Canadian evidence on nabilone invigorated further research into cannabis for PTSD. After Jetly’s RCT, other investigators launched studies looking at different formulations and contexts. For example, observational studies and case series examined nabilone use in broader PTSD populations (including a notable Canadian cohort study that found approximately 72% of patients had either total cessation or reduction of nightmares with nabilone treatment). Researchers also began asking if other cannabinoids or cannabis-based products could yield similar benefits. This paved the way for trials combining THC and CBD, studies on smoked or vaporized cannabis in veterans, and investigations into how cannabinoids might synergize with therapy for PTSD. By breaking the ice, Canada’s nabilone research gave scientists worldwide a foundation to build upon. Internationally, we saw growing interest: for instance, Europe and the U.S. eventually initiated their own controlled studies (one recent multicenter trial in 2023 is testing oral THC for PTSD-related nightmares in a veteran population, directly inspired by earlier findings). None of this momentum would likely have been possible without that early Canadian leadership in the field.

Looking Ahead

Even with the progress to date, much remains to be explored. Jetly’s trailblazing study was small, and its positive results call out for larger, multi-site trials to confirm and extend the findings. Future research will need to determine whether cannabinoids like nabilone can impact not just nightmares but the broader spectrum of PTSD symptoms and functional outcomes over the long term. Some important directions for the next generation of studies include:

• Beyond Nightmares: Evaluate whether nabilone (or other cannabinoid therapies) can reduce overall PTSD severity and daytime symptoms, not just sleep disturbances. Researchers are interested in whether improved sleep and nightmare relief eventually translate into lower anxiety, fewer flashbacks, or better mood during the day.

• Combination Therapies: Study the effects of combining THC analogs with CBD (cannabidiol) or other compounds. CBD, a non-intoxicating cannabinoid, might complement nabilone by reducing anxiety or countering side effects, and combination therapy could broaden the benefits for veterans with PTSD.

• Long-Term Use and Safety: Conduct longer-duration trials to observe how sustained use of nabilone affects patients over months or years. Since most studies so far have been under 9 weeks, understanding tolerance, continued efficacy, and any long-term side effects is vital. This is especially important if veterans are to use these medications chronically.

• Integration into Rehabilitation: Investigate how cannabinoids can be integrated into structured PTSD treatment programs. For example, trials could test nabilone as an adjunct during trauma-focused therapy – does controlling nightmares and improving sleep help patients engage more successfully in counseling or physiotherapy? Studies that measure functional outcomes (return to work, relationship stability, etc.) will shed light on the real-world impact of adding cannabinoid therapy to standard care.

As of 2025, Canada stands as a unique success story in the realm of cannabinoid-based mental health treatments. Nabilone’s journey – from a niche anti-nausea drug to an evidence-backed PTSD nightmare remedy – is a testament to Canada’s clinical leadership and regulatory foresight. The research spearheaded by Canadian veterans’ health experts proved that a science-first approach to cannabis could yield tangible benefits for patients in need. In the meantime, nabilone remains a symbol of this progress: a pharmaceutical cannabinoid, tested in veterans, approved by regulators, and backed by meaningful clinical data. Its impact has been felt not only by the individual veterans whose sleep it improved, but also by the wider medical community grappling with how to help those with treatment-resistant PTSD.

In retrospect, what nabilone demonstrated was far more important than just the alleviation of nightmares in a handful of patients. It provided proof that cannabinoids could be studied and utilized within the strictures of modern medicine – that a drug derived from cannabis could meet the standards of safety and efficacy and make a difference for a challenging condition. This proof-of-concept has opened doors. Today, researchers and policymakers around the world view cannabinoid therapy for PTSD with far less skepticism than they did a decade ago, thanks in large part to the Canadian evidence. For veterans suffering the long aftermath of trauma, this means a broader horizon of hope: new options on the way, and a growing recognition that innovative treatments like cannabinoids might play a key role in their healing journey.

References:

• Jetly, R., Heber, A., Fraser, G., & Boisvert, D. (2015). The efficacy of nabilone, a synthetic cannabinoid, in the treatment of PTSD-associated nightmares: a preliminary randomized, double-blind, placebo-controlled cross-over design. Psychoneuroendocrinology, 51, 585–588. PMID: 25467221. degruyterbrill.comdegruyterbrill.com

• Sheehy, S., et al. (2025). Cannabis Use Characteristics and PTSD-Related Outcomes Among Canadian Veterans With Chronic Pain. Journal of Veterans Studies, 11(1), 30–46. journal-veterans-studies.org