Across Minnesota, Israel, Brazil and Australia, researchers are asking important questions about cannabinoids and autism. What do randomized clinical trials actually show? What can real-world patient reports tell us about anxiety, sleep, behavior and daily life? And what does the endocannabinoid system have to do with the conversation?
This research edition of Stardust Field Notes examines the original publications behind our 13-slide educational series, including Minnesota’s October 2026 report on 1,811 autistic patients, Israel’s landmark 150-participant randomized trial, Australia’s 2026 HARMONY clinical study, Brazil’s 60-child trial and a 2025 meta-analysis of 276 participants. The focus is on study design, specific outcomes and transparent source attribution.
At a glance: what the research covers
- Medical cannabis program data: symptom scores and patient experiences reported in Minnesota.
- Randomized controlled trials: differences between specific cannabinoid formulations and placebo in Israel, Brazil and Australia.
- Crossover trials: comparisons of CBD oil and placebo within carefully structured treatment periods.
- Systematic reviews: pooled evidence assessing social responsiveness, disruptive behavior, anxiety and sleep.
Minnesota’s 2026 autism report: 1,811 enrolled patients
Published on October 1, 2026, the Minnesota Office of Cannabis Management report examined first-time patients who listed autism spectrum disorder as a qualifying condition between August 2018 and July 2024. There were 1,811 enrolled patients; 1,645 (90.8%) made at least one medical cannabis purchase. The report combines enrollment, purchasing and patient symptom evaluations to describe outcomes in a real-world program.
The size and longitudinal program setting make the report notable. It remains an observational analysis: without random allocation to cannabis or an untreated control group, symptom changes cannot establish that cannabis alone caused those changes. Read Minnesota’s report and executive summary.
Minnesota: reported anxiety and depression improvements
Among patients beginning with moderate-to-severe anxiety, 57% experienced at least a 30% reduction in their anxiety score within four months of their first medical cannabis purchase. For patients with moderate-to-severe depression, 63.4% reported the same threshold of improvement within four months.
The persistence measure is different from the initial four-month response: overall, 34.3% of the relevant patients sustained meaningful anxiety-score improvement for at least four months after initial improvement, while 42.9% sustained depression-score improvement. These percentages have different denominators and should not be conflated. Source: Minnesota OCM research announcement.
Minnesota: sleep, fatigue and daily function
The report also identified patients whose moderate-to-severe symptoms improved and stayed improved: 37.3% for disturbed sleep and 34.4% for fatigue. Minnesota's report noted similar proportions of sustained improvement among adult and pediatric patients for several symptom categories, including anxiety, depression and fatigue.
These findings address co-occurring experiences that matter in everyday life, rather than treating autism itself as a single symptom to be eliminated. Patient-reported sleep, fatigue and mood outcomes are valuable, but they are not interchangeable with standardized clinician-rated measures or proof of causality. Source: full Minnesota Office of Cannabis Management report (PDF).
Israel 2021: randomized trial of 150 participants
Aran and colleagues published a double-blind, placebo-controlled, proof-of-concept clinical trial involving 150 autistic participants ages 5–21. Investigators compared a CBD-rich whole-plant cannabis extract containing CBD and THC in a 20:1 ratio, a purified CBD:THC preparation at the same ratio and placebo. The trial evaluated a 12-week treatment period and subsequent crossover.
On a clinician-rated measure anchored to disruptive behavior, 49% of evaluated participants given the whole-plant extract were rated “much” or “very much” improved, versus 21% given placebo (p = 0.005). That comparison involved 45 and 47 evaluated participants, respectively—not 49% of everyone enrolled. A separate primary questionnaire outcome did not show a significant between-group difference, so the overall results were mixed. Source: Aran et al., Molecular Autism (2021).
Israel: social responsiveness measured separately
The same Israeli randomized trial reported greater median improvement in Social Responsiveness Scale (SRS-2) scores with the whole-plant extract: 14.9 points among 34 evaluated participants versus 3.6 points among 36 placebo participants (p = 0.009). These are median point changes, not percentages and not the mean.
The purified cannabinoid group did not replicate every result, and other outcomes were not consistently significant. Formulation and measurement choices matter. Source: Aran et al., full randomized trial.
How it may work: the endocannabinoid system and autism research
The endocannabinoid system (ECS) is a biological signaling network comprising endogenous cannabinoids, enzymes and receptors such as CB1 and CB2. CB1 receptors are particularly abundant in the central nervous system, where endocannabinoid signaling can regulate neurotransmitter release; CB2 signaling is prominent in immune-related pathways, among other sites.
These pathways have prompted investigations into neural signaling, sensory processing, stress responses, sleep and the biology of autism. The ECS slide presents a mechanistic research framework—not proof that any one cannabis product normalizes autistic neurology. Clinical outcomes must still be tested separately from biological hypotheses.
Australia 2026: the HARMONY randomized clinical trial
The corrected Australia image features the HARMONY trial, reported by Keating and colleagues in Neurotherapeutics in 2026. The study enrolled 61 autistic children with moderate-to-severe support needs; 54 completed its eight-week randomized, double-blind, placebo-controlled phase. Investigators studied NTI164, a full-spectrum medicinal cannabis extract containing less than 0.3% THC.
Compared with placebo, researchers reported statistically significant improvements in overall clinical severity, adaptive functioning, social responsiveness and affective symptoms. Caregivers also described improvements in family experiences and quality of life. As with any formulation-specific clinical study, these findings describe NTI164 under the study protocol; they should not automatically be generalized to every CBD product. Source: Keating et al., HARMONY trial (2026).
Brazil 2024: 60 children in a randomized 12-week trial
A Brazilian randomized, double-blind, placebo-controlled trial included 60 autistic children ages 5–11 receiving either CBD-rich cannabis extract or placebo for 12 weeks. Researchers reported statistically significant differences on several measured outcomes: social interaction (p = 0.0002), anxiety (p = 0.016), psychomotor agitation (p = 0.003) and concentration (p = 0.01).
The concentration finding was significant only in the mild-ASD subgroup. The paper also reported differences in number of meals per day (p = 0.04). These p-values describe statistical results, not the percentage of children improved. Source: da Silva Júnior et al., Trends in Psychiatry and Psychotherapy (2024).
CBD crossover trial, 2026: social relating, anxiety and parental stress
Parrella and colleagues studied 29 autistic children ages 5–12 in a randomized, double-blind, placebo-controlled crossover trial of CBD oil containing terpenes. Participants completed two 12-week intervention periods separated by an eight-week washout. The article appeared online in December 2025 and in a 2026 journal issue.
Relative to placebo, the researchers found improvements in secondary measures of social relating (adjusted p = 0.024), anxiety (adjusted p = 0.002) and parental stress (adjusted p = 0.044). Importantly, the primary social responsiveness outcome was not statistically significant (p = 0.125). Reporting both is essential to understanding the study. Source: Parrella et al., Autism Research (2026).
Israel 2019: six-month real-world study of 188 patients
In the prospective observational report published by Bar-Lev Schleider and colleagues in Scientific Reports, 188 autistic patients began medical cannabis treatment. The predominant preparation was a CBD-rich oil containing approximately 30% CBD and 1.5% THC. At six months, 155 patients remained on treatment, and 93 completed the outcome questionnaire.
Among those 93 six-month respondents, 30.1% reported significant improvement, 53.7% moderate improvement, 6.4% slight improvement and 8.6% no change. The study provides a picture of caregiver/patient experiences, with no placebo comparison and potential follow-up response bias. Source: Bar-Lev Schleider et al., Scientific Reports (2019).
What happens when randomized trial results are combined?
A 2025 systematic review and meta-analysis combined 276 participants across three randomized controlled trials of CBD-rich cannabis extracts for autism. Pooled estimates favored the cannabinoid preparations for social responsiveness (standardized mean difference, SMD = −0.75; p < 0.01), disruptive behavior (SMD = −0.36; p = 0.02) and anxiety (SMD = −0.33; p = 0.03).
The pooled estimate for sleep quality did not meet conventional statistical significance (SMD = −0.19; p = 0.21). Although the synthesis helps compare studies, it drew on only three trials, with differing formulations and methods, so pooled results should be understood alongside those limitations. Source: 2025 systematic review and meta-analysis, European Psychiatry.
Research conclusion: the science is moving forward
The clearest message is not that every cannabinoid formula produces the same outcome. It is that international researchers are measuring specific changes in anxiety, social relating, behavior, adaptive function, sleep and everyday well-being using increasingly diverse clinical methods.
Randomized trials supply comparisons against placebo; observational reports illuminate what patients and families report outside a controlled trial; systematic reviews help identify patterns across studies. These evidence types complement one another without becoming interchangeable. The next generation of research can clarify which formulations, participants, outcomes and durations are most relevant.
Real research. Real patients. Better questions.
Science Meets Stardust™ — Mandi Cruz Media
Frequently asked questions about cannabis and autism research
Has cannabis been studied for autism in randomized trials?
Yes. Published randomized studies include the Israeli 150-participant trial, Brazil’s 60-child trial, the HARMONY trial in Australia and a 29-child CBD crossover trial. Their formulations and measured outcomes differ.
What outcomes have researchers examined?
The studies assess specific outcomes such as social responsiveness, anxiety, disruptive behavior, adaptive functioning, disturbed sleep, fatigue and family stress; each tool measures something different.
Are medical cannabis program findings the same as placebo-controlled results?
No. Patient-program reports capture experiences in routine care; randomized placebo-controlled trials can more directly assess differences associated with a particular intervention.
What is the role of the endocannabinoid system?
The ECS helps regulate cellular signaling, particularly in neural and immune pathways. Its possible involvement in autism-related mechanisms is an active area of study rather than a standalone clinical conclusion.
Original studies and reports
- Minnesota Office of Cannabis Management. Autism Spectrum Disorder Patients in the Minnesota Medical Cannabis Program (2026).
- Aran A et al. Cannabinoid treatment for autism: a proof-of-concept randomized trial. Molecular Autism (2021).
- Keating BA et al. The HARMONY study of NTI164. Neurotherapeutics (2026).
- da Silva Júnior EA et al. Randomized CBD-rich extract trial in autism. Trends in Psychiatry and Psychotherapy (2024).
- Parrella N-F et al. CBD crossover trial for social relating, anxiety and parental stress. Autism Research (2026).
- Bar-Lev Schleider L et al. Real life Experience of Medical Cannabis Treatment in Autism. Scientific Reports (2019).
- Systematic review and meta-analysis of randomized CBD extract trials in autism. European Psychiatry (2025).
Research compiled and interpreted by Mandi Cruz Media, evidence-based cannabis education. Published October 2026. Explore more education from Mandi Cruz Media.
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