There is potential for marijuana to treat some symptoms of autism. Proponents believe marijuana may be able to calm abnormal brain activity, improve cognitive functioning, and increase socialization abilities in people with autism.

In 2021, marijuana is still illegal at the federal level. As a result, there are limits to research studies on marijuana due to federal restrictions.

What Is Cannabis?

Cannabis comes from Cannabis sativa, which is one of the oldest cultivated plants in the world. In the 19th century, medical practitioners started to use cannabis to treat mental health disorders and other conditions.

Despite many states and a number of countries legalizing the recreational use of small amounts of marijuana, the drug remains illegal under federal law. It is classified by the Drug Enforcement Administration as a Schedule I substance, the highest level of drug classification.

Because of this, there is a “conflicting spiral” on the widespread medical use of marijuana. The federal restrictions mean that there is not enough scientific evidence to establish its efficacy, but the government claims that there is not enough scientific evidence to lift the restrictions on cannabis. Until this deadlock is resolved, the research on marijuana for autism remains in a mostly hypothetical stage in 2021, with only small studies suggesting the way forward.

As an example, a 2019 article from BMC Psychiatry notes that “there is currently insufficient evidence for cannabis use in [autism spectrum disorder],” but the researchers noted that there is an “urgent need” for more studies and tests to look at the risks, benefits, and impact of using marijuana to treat the symptoms of autism spectrum disorder.

This research can add to the potential of more treatment and therapy options for people with autism. It might also prevent negative outcomes from unregulated and unmonitored marijuana use by families who want to reduce the symptoms of autism in their loved ones.

An Example From Epilepsy

Some progress is being made. In 2018, the Food and Drug Administration approved Epidiolex, a cannabis-based oral medication for the treatment of an uncommon, but severe, form of childhood-onset epilepsy. Clinical trials of the medication showed that it was successful in decreasing seizure activity by up to 50% in patients with the disorder.

Epidiolex contains cannabidiol (CBD), one of the major chemical compounds in the Cannabis sativa plant.

The success of Epidiolex was partly due to GW Pharmaceuticals, a biopharmaceutical company in England that grew and provided the cannabis used in its clinical trials. It remains the only instance of the FDA approving any cannabis-based medication.

Seeing how well Epidiolex worked, GW Pharmaceuticals next worked on developing another cannabis-based drug to treat autism symptoms. Epilepsy and autism share many behavioral symptoms. The founder of the company told CNN that the two conditions “are on the same continuum,” specifically mentioning the poor language skills, socioemotional inhibition, and loss of cognitive function that are common to both.

CBD & Abnormal Electrical Activity

The cannabis cultivated by GW Pharmaceuticals is shipped from the United Kingdom to Dr. Eric Hollander, the director of the Autism and Obsessive Compulsive Spectrum Program, and Anxiety and Depression Program, at Montefiore Hospital in New York.

This is because Dr. Hollander is one of the physicians who thinks that cannabidiol has promise for treating the symptoms of autism spectrum disorder. He bases this on the effectiveness that CBD has shown in reducing seizure activity.

Autism causes “abnormal electrical activity” in the brain (“multiple neural system dysfunctions,” according to the Journal of Neurodevelopmental Disorders), even though patients with autism will likely not have seizures. Past research has shown that when receiving anticonvulsant medication that decreases that electrical activity, “some of the disruptive behaviors actually get better.”

As an autism researcher, this information caught his attention. Because CBD helps with epilepsy by calming the brain’s electrical activity (for which it might be useful in treating anxiety disorders like social anxiety disorder), he and other researchers theorize that this might prove helpful in controlling the self-injury, meltdowns, and aggression that autistic individuals tend to experience.

Learning From Epilepsy Treatments

The full pathologies of either condition are not fully understood, but Hollander theorizes that autism and epilepsy could have similar causes. Using CBD to treat the associated symptoms of autism could offer a breakthrough in helping patients curb the disruptive behaviors that are characteristic of autism spectrum disorder.

Tests on animal models that were similar to autism found that cannabidiol had notable effects on decreasing seizures and also on improving social functioning, increasing cognitive functioning, and cutting down on repetitive or compulsive behavior. This raised immediate questions on whether cannabidiol could be applied to human subjects with autism spectrum disorder, especially given that a CBD-based medication was useful in helping human subjects who had epilepsy.

Unknown Factors

Much remains unknown about autism, and the medicinal use of marijuana is a hot-button issue. The mainstream medical community remains cautious, yet optimistic, about turning to medications derived from cannabis to treat autism symptoms. Another doctor, not involved in Dr. Hollander’s research, told CNN that he was hopeful about the initial reports of using CBD for autism patients.

Even though cannabis compounds show promise to encourage further research, autism is such a diverse condition that some presentations of the disorder might not respond to CBD medication, or they might respond with unexpected effects.

In the same way that autism affects different people in very different ways, CBD might similarly benefit only a subset of autism patients and without any verifiable standardization. One of the challenges facing doctors and therapists will be to determine which patients will respond best to this treatment and which symptoms have the best chance of improving.

It may be the case that marijuana for autism symptoms might not offer any therapeutic value to a majority of people with autism. Like most medication applications, doctors will need to supervise patients who try these new treatments and amend the treatment plan as needed.

Israeli Research

Other recent research on marijuana for autism has yielded encouraging results, but there are caveats.

For example, in “Real life Experience of Medical Cannabis Treatment in Autism: Analysis of Safety and Efficacy,” a 2019 article in Scientific Reports, scientists in Israel (where medical cannabis is recognized by the national government) have been able to conduct experiments and discover that cannabis oil is “safe and effective” for the treatment of autism symptoms. After six months of receiving the product, 30% of the 188 autistic teens in the study experienced a significant improvement in their symptoms. Over 50% said they enjoyed a moderate improvement in symptoms.

However, the study was supported by the largest national producer of medical cannabis in Israel, and many of the authors worked for the company. Other observers raised questions about the short-term nature of the follow-up study. As a result, additional studies with controls are needed to validate the findings.

Nonetheless, other studies conducted around the world (albeit in limited contexts) have supported the findings of the 2019 Scientific Reports article. Even as researchers writing in Frontiers in Psychology have noted the limitations of their own work, they concluded their article by saying, “Parents’ reports suggest that cannabidiol may improve ASD comorbidity symptoms” and increase social responsiveness in autistic children.” These findings have been supported by other studies.

Another study, also out of Israel, published in the Neurology journal noted that out of a study size of 60 children, over 60% of patients experienced an improvement in their behavioral issues after receiving cannabis as part of their therapy.

Tools in the Toolbox

The lead researcher similarly warned that parents of children with autism should wait for more data before turning to medical cannabis as a therapy option. It is still too early to tell what the overall effects will be.

There were also downsides to the cannabis exposure. Children who received the medication experienced a loss of appetite, fatigue, and irregular sleep patterns. Parents and doctors will have to weigh whether the benefits of cannabis outweigh these negative side effects for some children.

Nonetheless, autism advocates are optimistic, if hesitant. The president of the International Society for Autism Research, who reviewed the study, praised the work of the researchers but encouraged caution when considering marijuana for autism, “given the report of significant rates of unwanted side effects.”

Having more treatment options allows parents and autistic individuals to make better, more informed choices. Even the researchers writing in the Neurology article agreed that cannabis for autism is “not a miracle treatment,” but “another tool in our toolbox.”

Marijuana for Autism in 2021?

As long as the federal government resists loosening its restrictions on cannabis for more research and therapeutic applications, there will remain a scarcity of robust, large, and placebo-controlled trials. Without this needed research to back up its use, it’s unlikely that cannabis will receive the green light in therapies.

In 2018, the Global Pediatric Health journal noted that despite sensationalized media claims about cannabis being the breakthrough drug for autism treatment, there is more anecdotal evidence for the benefits of CBD than there is empirical data. It might turn out that the buzz about marijuana for autism is overblown, and the actual results of studies don’t support its widespread use. We just don’t know yet.

While work is being done to open up the research more (like a CBD-autism clinical trial recruiting participants at the University of California, San Diego), it will likely take more time until there is real scientific confidence and consensus that marijuana will be a beneficial and legitimate addition to the treatment toolbox for autism.

Until we know more, talk to your doctor about evidence-based autism treatments. Applied behavior analysis (ABA) therapy is the backbone of autism treatment, but other therapies (like speech therapy, occupational therapy, and even physical therapy) can complement your treatment plan. In some cases, medications may be recommended for co-occurring issues.

Your treatment team will lead the way on the best path forward to manage your autism symptoms.


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