Cannabis and autism, explained
by Peter Hess / 7 September 2020
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Over the past decade, autistic people and their families have increasingly experimented with medical marijuana and products derived from it. Many hope these compounds will alleviate a range of autism-related traits and problems. But scientists are still in the early stages of rigorous research into marijuana’s safety and effectiveness, which means that people who pursue it as treatment must rely mostly on anecdotal information from friends and message boards for guidance.
Here we explain what researchers know about the safety and effectiveness of cannabis for autism and related conditions.
What is medical marijuana?
Medical marijuana generally refers to any product derived from cannabis plants — including dried flowers, resins and oils — that has been recommended by a doctor. It may be consumed directly or infused into an array of foods, lozenges and candies. These products have become popular among autistic people and their families for treating a broad swath of conditions, including insomnia, epilepsy and chronic pain.
Depending on the strain of the plant and the processing methods used, these products contain varying levels of active ingredients, including tetrahydrocannabinol (THC) — responsible for the ‘high’ associated with marijuana — and cannabidiol (CBD), which is minimally psychoactive. Much of the research on medical applications focuses on CBD. There are also more than 500 other compounds in marijuana that may affect people’s behavior and cognition 1 .
Is medical marijuana legal?
Yes and no. Federal law in the United States classifies marijuana and its derivatives as ‘Schedule 1’ drugs, meaning that they have no accepted medical use and a high potential for abuse. Schedule 1 drugs are illegal, and research on them requires labs to follow strict security protocols and adhere to regular facility inspections.
In 33 states, along with the District of Columbia and Puerto Rico, however, people can legally buy and use medical cannabis for certain approved conditions, such as seizures and sleep problems, although the list of qualifying conditions varies by state. These same states, plus 13 others, also allow CBD oil. Fourteen states plus Puerto Rico have approved medical marijuana for autism, and some additional states may allow it for autistic people at a doctor’s discretion.
Under U.S. federal law, CBD products manufactured from industrial hemp are legal as long as they contain no more than 0.3 percent THC. And in some states, CBD oil is permitted to contain up to 5 percent THC.
In many states where medical marijuana is legal, licensed dispensaries sell products that have been tested by accredited laboratories to verify the presence of active ingredients and the absence of contaminants. Some states permit individuals or their licensed caregivers to grow their own cannabis plants for personal use. Most states in the U.S. require people who use medical marijuana to register and get a special identification card.
In many European countries, as well as in Australia, Canada, Israel and Jamaica, medical cannabis is legal, with specific laws varying from country to country.
Are there any cannabis-derived drugs approved to treat autism or related conditions?
To date, the U.S. Food and Drug Administration has approved only one cannabis-derived drug: Epidiolex. It is a liquid cannabis extract containing purified CBD that can decrease seizures in people with Dravet syndrome or Lennox-Gastaut syndrome — severe forms of epilepsy that are sometimes accompanied by autism — and in those with tuberous sclerosis complex. It is available only by prescription, and only for these three conditions.
GW Pharmaceuticals, the company that makes Epidiolex, is conducting a trial of the drug for Rett syndrome, a neurodevelopmental condition related to autism. The Rett syndrome trial is not focused on alleviating seizures, but on improving cognitive and behavioral problems. The company is also recruiting autistic children and teenagers for a phase 2 trial of cannabidivarin, another component of cannabis. That trial will examine cannabidivarin’s effect on a range of traits in autistic children, including repetitive behaviors, and on quality of life.
How might cannabis help autistic people?
Epidiolex’s success has spurred many parents to try marijuana and cannabis extracts for seizures, behavioral issues and other autism-related traits in their children, but experts warn that these drugs remain largely untested for such purposes. Some studies on cannabinoids have shown promising results in animal models and in early-stage clinical trials, but this research does not yet support their widespread use.
Cannabis’ active ingredients are thought to exert their effects by binding to proteins called cannabinoid receptors in the brain: THC activates the CB1 and CB2 receptors, whereas CBD seems to block them 2 .
Both types of cannabinoid receptors are located in neurons in the brain and throughout the body. The brain contains more CB1 than CB2 receptors, and the activation of each receptor type affects a range of ion channels and proteins involved in cell signaling 3 . The ultimate effects of cannabinoid receptor activation depend on which body system they belong to. For instance, the activation of CB1 receptors in the brain can either increase or decrease neuron excitability, depending on which kind of neuron a cannabinoid binds to; activation of CB2 receptors in the digestive system can decrease inflammation 4,5 .
Blocking the CB1 receptor can relieve seizures and memory issues in a mouse model of fragile X syndrome, a condition related to autism, according to a 2013 study in Nature Medicine 6 . A 2018 clinical trial of a synthetic CBD drug by the drug maker Zynerba showed significant improvements in anxiety and other behavioral traits in people with fragile X. Cannabinoid receptor activation has also been shown to lead to memory improvements in fragile X mice 7 .
Research has also demonstrated that CBD alleviates seizures in children with CDKL5 deficiency disorder, an autism-linked condition that is characterized by seizures and developmental delay. CBD also lessens seizures and improves learning and sociability in a mouse model of CDKL5 deficiency disorder.
Complicating the picture, CBD alone may not be sufficient for cannabis’ therapeutic effects. A 20-to-1 ratio of CBD to THC relieves aggressive outbursts in autistic children, a 2018 study suggests 8 . This same ratio of compounds significantly improved quality of life for some children and teenagers with autism in a 2019 study 9 . Specifically, researchers observed significantly fewer seizures, tics, depression, restlessness and outbursts. Most participants reported improvements, and about 25 percent of participants experienced side effects such as restlessness.
Cannabis may have effects that go beyond the cannabinoid receptors, too. Mice that ingested CBD over extended periods of time displayed changes to DNA methylation in sections of the genome associated with autism, a 2020 study showed 10 . The researchers suggested that epigenetic changes may be at least partly responsible for CBD’s behavioral effects, though they did not directly examine the mice’s behavior.
Is cannabis safe?
It’s unclear. Large doses are usually not fatal, but taking it regularly may have long-term effects.
Based on the clinical trials of Epidiolex, the FDA warns that the drug could cause elevated liver enzymes, which can be a sign of liver damage. This is especially likely in people who take Epidiolex and the epilepsy drug valproate at the same time.
CBD is considered minimally psychoactive, but many preparations of it contain undisclosed amounts of THC, which may lead to inadvertent intoxication and impairment.
Many studies have shown that cannabis treatment carries only minor side effects such as sedation or restlessness, but these studies have not looked at long-term side effects. Researchers still don’t have a solid grasp on how the active ingredients in marijuana actually affect the brain, nor do they know how these compounds might impact a child or teenager’s developing brain or interact with other medications.
Some research has shown that recreational marijuana use beginning in one’s teenage years can have negative long-term effects on cognition 11 . But experts note that the dosages used for medical purposes are often quite lower than those used in a recreational context.
Are some cannabis products safer or more effective than others?
Many people who self-administer cannabinoids for epilepsy or other conditions cultivate it at home. Others purchase it directly from companies rather than buying it at state-licensed dispensaries, and research has shown that these products are not created equal.
The actual potency of CBD products varies widely from their advertised concentrations, according to a 2017 study in JAMA, and some products contain more than the legal limit of THC — potentially enough to cause intoxication, especially in children 12 . Less than one-third of the products tested contained within 10 percent of the advertised CBD concentration, and THC was detected in about 21 percent of samples.
In a presentation at the 2020 meeting of the American Academy of Neurology, researchers concluded that ‘artisanal’ CBD products available for purchase online and in health-food stores are not as effective at controlling seizures as pharmaceutical-grade CBD.
Autistic people and their families are increasingly experimenting with marijuana to try to ease problems such as insomnia, epilepsy and chronic pain — and traits of autism. But there is little evidence for its safety or effectiveness.
CBD oil and asperger syndrome
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- Research overview
- The studies
- Patient perspectives
- What the experts say
- Bottom line
Often regarded as a high-functioning form of autism, Asperger syndrome is part of the autism spectrum disorder (ASD) group. Typical symptoms of Asperger syndrome include delayed language development and social anxiety or disconnection.
Researchers have uncovered that a significant percentage of children with Asperger syndrome have been successfully treated with CBD-rich oil. Photo by: Gina Coleman/Weedmaps
Prescription medications for ASD, most notably risperidone, often come with serious side effects that affect the body, mind, and behavior, sometimes even precipitating violent outbursts. Thus, there is a growing need in the ASD community for a functional treatment option without such adverse effects.
Full-spectrum cannabis oil, derived from cannabidiol (CBD)-rich cultivars, utilizing the cannabinoid-rich flowers to maintain beneficial terpenes during the extraction process is showing some promise as a viable treatment option for patients with Asperger syndrome and their caregivers.
Whole-plant CBD oil has demonstrated potential for treating numerous incurable conditions. Among them are epilepsy, cancer, and Parkinson’s disease. Some studies have indicated that CBD oil may also serve as a treatment for ASD, including Asperger syndrome.
One study published in 2013 in the Journal of Autism and Developmental Disorders documented that children with autistic disorders have an increased number of cannabinoid receptors on their circulating white blood cells, suggesting an imbalance in their endocannabinoid systems (ECSs). Measuring endocannabinoid levels has been difficult because these compounds are made on-demand when needed and then broken down as soon as they are used.
Another study, by researchers from Stanford University in California and published in Molecular Autism in 2018, documented that children with autism have lower levels of anandamide compared with children not diagnosed with autism. Anandamide is one of the brain’s endocannabinoids, and it works to balance the neurotransmitter messages that are sent between cells. Without this compound, cells send inappropriate or overwhelming messages. This is the basis of treating autism with cannabis, as both of these studies demonstrate an endocannabinoid deficiency in children with ASD.
Studies indicate that CBD-rich cannabis oil may serve as a legitimate treatment for autism spectrum disorder, including Asperger syndrome. Photo by: Gina Coleman/Weedmaps
Further, a 2018 Israeli study examined the effects of oral CBD and THC on 60 children with autism. Researchers reported strong improvement in behavioral outbreaks in 61% of the children following treatment. However, fewer than half of the children experienced notable improvements in communication and anxiety. In either case, the sample size was limited, only one variety of cannabis was tested, and the results may not offer definitive answers. The scientists were nonetheless encouraged by the study and are now conducting a clinical trial with 120 children.
Beyond clinical trials, researchers have uncovered other evidence that a significant percentage of children with Asperger syndrome and other ASD diagnoses have been successfully treated with CBD-rich cannabis oil. Survey results published in 2019 in Remedy Review revealed that more than 40% of parents of children with ASD have tried some type of CBD treatment.
The most popular methods of administering CBD oil were via water (43%) and by inserting drops directly into the mouth (32%). The most common patient benefits reported by those surveyed were improved mood (56%), less anxiety (53%), and stress relief (45%). Finally, the parents whose children used CBD were nearly 55% more likely to rate the treatments as moderately or extremely effective compared to those using prescription medications.
For parents who feel they have exhausted all treatment options without success, a positive outcome with cannabis oil can seem remarkable. Rachel Anderson, whose son has a rare form of epilepsy and ASD, told Healthline in 2019, “we had tried six or seven pharmaceutical drugs. None of them worked, or if they did, they had serious side effects that made life miserable for all of us.”
Anderson claims the CBD oil has reduced her son’s seizures while addressing his ASD symptoms. She said, “My son is horribly anxious, but when we give him his CBD, he’s cool as a cucumber.”
What the experts say
Many expert opinions appear to align with the stories that parents are conveying. Dr. Bernard Rimland, who died in 2006, was the director of the Autism Research Institute in San Diego and wrote extensively about the potential of medical marijuana as a treatment for autism and associated disorders as editor of Autism Research Review International.
There is abundant anecdotal evidence to indicate that CBD-rich cannabis oil is an effective treatment option for Asperger syndrome and other forms of autism. Photo by: Gina Coleman/Weedmaps
Today, Rimland’s ideas are making progress. Other medical practitioners at the Autism Research Institute agreed with Rimland, and cannabis is listed as a treatment for ASD on the institute’s website. Indeed, the notion of using CBD oil and other cannabis treatments for Asperger syndrome is growing in the autism community. In 2018, Autism Speaks, a research and advocacy organization for autism spectrum disorders, hosted the first scientific conference on ASD and cannabis. Held in New York, the conference addressed the need for more research into the effects of cannabis on ASD.
“As more states legalize cannabis, we know that a growing number of families affected by autism are considering these products to relieve severe behavioral symptoms, seizures and other challenging autism-related conditions,” said Thomas Frazier, Ph.D., chief science officer for Autism Speaks. “But while anecdotal reports of benefit are common, we lack sufficient scientific evidence on effectiveness and risks.”
There is abundant anecdotal evidence to indicate that CBD-rich cannabis oil is an effective treatment option for Asperger syndrome and other forms of autism, but more in-depth studies with large sample sizes are needed to establish scientific proof.
CBD oil and asperger syndrome Copy article link to clipboard. Link copied to clipboard. Contents Research overview The studies Patient perspectives What the experts