Autism: Medical Cannabis Is Linked to Reduced Anxiety

A new study conducted by the’Minnesota Office of Cannabis Management (OCM) provides one of the most comprehensive datasets to date on the use of the Medical cannabis for people with autism. Based on several years of data from the U.S. government’s medical program, researchers observed reported improvements in various symptoms frequently associated with the autism spectrum disorder (ASD), particularly anxiety, depression, and sleep disorders.

The report covers the first six years during which autism was recognized as a condition that qualified individuals for the medical cannabis in Minnesota. Its objective was not to conduct a clinical trial, but to analyze patients’ real-world experiences, their purchases, changes in various symptoms, and reported adverse effects.

More than 1,600 medical cannabis patients studied

Between August 2018 and July 2024, 1,811 patients with ASD enrolled in Minnesota’s medical cannabis program for the first time. Of these, 1,645—or 90.8%—purchased medical cannabis at least once and constitute the primary population analyzed in the report.

The cohort is notable in particular for its young age. The average age at enrollment was 20 years, while 47.7% of the participants were under 18 years of age. Consumption patterns differed significantly by age: among minors, 85.3% of the products purchased were intended for oral administration, whereas inhaled products accounted for 68% of purchases among adults.

The choices in terms of cannabinoids also varied. Patients under the age of 18 primarily purchased oral products high in CBD compared to the THC, or with a more balanced ratio. Adults were more heavily represented among purchases of products with a high THC content.

Anxiety, the most commonly reported symptom

To assess patients' progress, the program used a self-assessment questionnaire covering eight symptoms: anxiety, loss of appetite, depression, sleep disturbances, fatigue, nausea, pain, and vomiting. Their severity was rated on a scale from 0 to 10. A reduction of at least 30% from the baseline score was considered a clinically significant improvement.

Theanxiety was particularly common. At the start of follow-up, 88.3% of the patients in question reported moderate to severe anxiety. Among them, 57% reported a decrease of at least 30% in their anxiety score within four months of their first purchase of medical cannabis.

Among the patients who initially achieved this level of improvement and for whom follow-up data were available, 67.4% maintained it for at least four additional months. When compared to all participants who initially suffered from moderate to severe anxiety, 34.3% therefore achieved and subsequently maintained this improvement.

Depression and Sleep: Other Improvements Observed

The findings are not limited to anxiety. Among participants who initially exhibited a depression moderate to severe; 63.4% reported a reduction of at least 30% in their score within the first four months. The report indicates that 41.3% of these patients ultimately achieved and maintained this improvement.

According to the study’s summary table, this proportion also reached 37.3% for sleep disorders and 34.41 TP3T for fatigue.

The testimonials collected by the program illustrate how some participants perceived these changes. One of them says, «I feel like my anxiety related to autism has eased a little. It helps me sleep a little better. It eases the pain caused by depression a little.»

Another testimonial describes: «Reduced anxiety, reduced aggressive behavior, reduced self-harming behavior, significantly improved sleep, fewer episodes, and a better appetite.»

Of course, these statements reflect individual experiences and, on their own, do not allow us to assess the effectiveness of a treatment.

Behavioral changes were also studied

The researchers also focused more specifically on behaviors associated with autism spectrum disorder using the ABC-2 questionnaire, which assesses, among other things, irritability, hyperactivity, lethargy, repetitive behaviors, and certain forms of inappropriate language.

Among the 46 patients who completed the questionnaire at the start of the program and again ten weeks later, a statistically significant decrease in scores was observed across all assessed domains. A lower score here corresponds to a reduction in the presence or severity of the behaviors measured.

However, this data should be interpreted with particular caution: these 46 participants represented only 3.9% of the individuals eligible for this part of the analysis. The authors themselves acknowledge that patients who reported benefits may be overrepresented in this sample.

A real-world study with significant limitations

The scope of the Minnesota registry makes these findings particularly noteworthy, but their nature observational It is not permissible to conclude that medical cannabis is the cause of the observed improvements.

All participants used medical cannabis. Therefore, there was no neither a placebo group nor a control group allowing for a comparison of their progression with that of patients who did not use them. The report also lacked sufficient information on other medications, therapies, or changes in treatment that might have influenced the symptoms.

Another notable limitation: a large portion of the cohort was underage. In some cases, the questionnaires were therefore completed by a parent or another adult, which means that the data combine patients’ self-reports with third-party assessments.

Data that, above all, underscore the need for research

The results from Minnesota ultimately contribute to the still limited and sometimes contradictory scientific literature on cannabinoids and autism. The report itself notes that the few clinical trials conducted to date have yielded varying results depending on the formulations used and the symptoms studied.

The authors therefore remain cautious: patients enrolled in a TSA reported a reduction in anxiety and, in one subgroup, a decrease in certain behavioral symptoms after starting the medical marijuana. However, these associations do not constitute proof of its therapeutic efficacy.

Another clinical trial provides additional evidence

These observations echo a clinical trial recently reported by Newsweed around the NTI164, an oral cannabis extract that is particularly rich in CBDA. The HARMONY trial—a randomized, double-blind, placebo-controlled study—involved children and adolescents with TSA. After eight weeks, the researchers observed, among other things, statistically significant differences in favor of NTI164 on certain measures of the’anxiety, mood, adaptive functioning, and social behavior. The results were, however, more mixed for other measures, particularly sleep.

Unlike the observational data from Minnesota, this trial therefore had a placebo group, but was based on a much smaller sample size: 54 participants completed its controlled phase. A Phase 3 study, Beyond Harmony, must now evaluate NTI164 in a group of up to 200 children. These two studies thus provide complementary insights, though they do not, at this stage, allow us to consider cannabinoids as an established treatment for autism.