Autism Spectrum Disorder (ASD) is one of the most prevalent neurodevelopmental disorders, affecting between 10 and 20 people per 10,000—though some estimates put that number closer to 72 per 10,0001. It is also very difficult to manage, as its treatment usually involves a wide range of social, communicative, physical, and medicinal therapies—and this is just to treat the core symptoms2
What makes ASD even trickier is its wide range of common comorbidities – conditions which occur simultaneously – which range from other mental disorders like ADHD and depression, to physical ones like epilepsy and sleep disruption3. While trying to treat these disorders ASD patients often ingest cocktails of pharmaceuticals, each with their own list of side effects. Many people with ASD and their loved ones are constantly asking: isn’t there something better they can take?
That’s where CBD can come into play.
In this article, we will explore the effectiveness of CBD as a potential treatment for ASD. In addition to investigating and illuminating the scientific literature available on such treatments, we will also briefly examine CBD’s usefulness in treating some of Autism’s most common comorbidities: ADHD and seizures.
First, though, we will take a look at the disease itself.
Table of Contents
- What is Autism Spectrum Disorder?
- What causes ASD?
- How can CBD help with Autism?
- What does scientific evidence have to say about treating ASD with CBD?
- Study 2
- What these two studies tell us
- How can CBD help with ASD’s comorbid disorders?
- What CBD products are best for the treatment of ASD?
What is Autism Spectrum Disorder?
Autism Spectrum Disorder (ASD) is a group of developmental disabilities that includes autistic disorder, Asperger’s Syndrome, and pervasive developmental disorder-not otherwise specified (PDD-NOS)4. Developmental disabilities are groups of conditions characterized by impairment in physical, learning, language, or behavior areas (or any combination of these)5.
People with developmental disabilities generally won’t reach “developmental milestones” (i.e. speaking their first word, playing with others) in the same time frames as people without them. Sometimes they won’t reach certain milestones at all6. For these reasons, developmental disabilities like ASD are almost always diagnosed in childhood.
What separates ASD from other developmental disabilities are a specific set of criteria set forth by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-V). Essentially, in order to be diagnosed with ASD, a person must exhibit persistent deficiency in three different areas of social communication and interaction7.
- The first area is social-emotional reciprocity, which is basically the normal flow of social interaction. Social-emotional reciprocity refers to how one person’s actions and emotions influence another person’s emotions and reactions during social exchanges like conversations8. Deficits in social-emotional reciprocity can manifest as an inability to hold back-and-forth conversations, failure to initiate or respond to social interactions, trouble sharing interests or emotions with others, or a number of other indicators.
- The second area is nonverbal communicative behaviors used in social interaction. Deficiency in this area emerges as abnormalities in eye contact and body language, as well as the inability to recognize such nonverbal cues in others. It can range in severity all the way up to a complete lack of facial expressions or any form of nonverbal communication9.
- The third area is in developing, maintaining, and understanding relationships. A person with deficits in this area has trouble adjusting their behavior to fit different social contexts, as well as difficulties making friends or taking interest in their peers10.
Alongside displaying deficiencies in all three of the areas outlined above, a person must also engage in at least two of four types of restricted, repetitive behavior to receive an ASD diagnosis. These include:
- Stereotyped or repetitive motor movements, use of objects, or speech. Examples include lining up or flipping toys and echolalia (the meaningless repetition of a word or phrase).
- Insistence on sameness, inflexible adherence to routines, or ritualized patterns of behavior. Examples include disproportionate distress or tantrums at small changes, insistence on walking the same routes or eating the same foods every day, and strict, cyclical thinking patterns.
- Highly restricted, fixated interests that are abnormal in intensity or focus. Examples include strong attachments to strange objects and fixation on excessively limited topics.
- Hyper- or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment. Examples include indifference to pain or fascination with textures.
Alongside the DSM-V’s criteria for ASD, there are many other signs and symptoms. A few additional symptoms include giving unrelated answers to questions, not understanding personal-space boundaries, flapping hands or spinning in circles, and an inability to pretend or imagine during playtime.
What causes ASD?
ASD has a number of biological, often prenatal factors involved, though none of them are unique to autism. What this can mean is that there are several diseases that are more prevalent in the ASD population (especially diseases that emerge before a person is born) than in the non-ASD population.
This leads scientists to believe that there is some correlation between these diseases and the ASD itself. Though this list of diseases is long and somewhat inconclusive, the conditions most strongly linked to ASD are intrauterine rubella, tuberous sclerosis, Cornelia de Lange’s syndrome, fragile X, and Angelman’s syndrome. After birth, conditions such as untreated phenylketonuria, infantile spasms, and herpes simplex encephalitis have been linked to ASD11. The proportion of ASD cases associated with these factors is roughly twenty-five percent12.
Apart from the one-fourth of people who may suffer from ASD because of one of the factors listed above, scientists believe the majority of people who develop ASD do so because of genetics. There are several studies linking higher rates of ASD between afflicted parents and their children, as well as amongst siblings.
One study on twins found a 60 percent concordance rate of ASD in monozygotic twins (i.e. identical twins—twins that result from the fertilization of a single egg that splits into two). This means that if one of the twins had ASD that there was a 60 percent chance the other had it as well, which, again, suggests a strong genetic basis for the disorder13. That being said, no “autism gene(s)” have been discovered as of yet.
How can CBD help with Autism?
In order to understand how CBD can help with ASD, it’s important to first understand a bit about the body’s endocannabinoid system—a system composed of endocannabinoids and endocannabinoid receptors. Cannabinoid receptors are complex protein structures on the surfaces of cells that permit communication and interaction between substances outside of the cell and substances within—they are part of the cellular communications network14.
Cannabinoids are plant substances that fortuitously interact with human endocannabinoid receptors; the cannabinoid is like a key, the receptor-like a lock that only specific keys fit into. So far scientists are aware of and focus on two main cannabinoid receptors in the body: CB1 receptors concentrated primarily in the central nervous system, and CB2 receptors located mostly in immune and gastrointestinal cells15.
Substances that bind to these receptors fall generally into three categories:
- Endocannabinoids which are naturally produced in the human body –examples include Anandamide (AEA) and 2–Arachidonoylglycerol (2AG)
- Phytocannabinoids, naturally produced by cannabis species including hemp. There are hundreds of phytocannabinoids found in Cannabis species.
- Cannabimimetics which can come from a variety of plants and imitate or mimic some of the effects of phytocannabinoids from Cannabis species.
Anandamide (AEA) and 2–Arachidonoylglycerol (2AG) are the two most prevalent endocannabinoids produced in the body, while delta-9 tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most abundant cannabinoids found in marijuana.
You may be asking: why exactly do I need to know all of this? How will this help me understand CBD’s relationship to ASD?
Well, AEA has been found to serve an important role in several behavioral functions pertinent to ASD in non-ASD brains. These include cognitive function, emotional regulation, social functioning, motivation, and reward processing16. It may be unsurprising that recent evidence is revealing a lower concentration of AEA in people with ASD compared to those without.
One study conducted on 112 children (59 with ASD, 53 without) showed “significantly lower” AEA concentrations on those afflicted with ASD17.
So, if we know that people with ASD have lower AEA levels, and we know that phytocannabinoids like CBD act on the same receptors as endocannabinoids like AEA, then the question becomes: what may CBD be doing—and is it beneficial—in people with ASD?
What does scientific evidence have to say about treating ASD with CBD?
Though research into treating ASD with CBD is relatively limited, there are a few studies available that show promising results. We will dive deeply into two of the major ones here.
Approximately 50 percent of children with ASD suffer from behavioral problems such as tantrums, self-injury, and violence18. A study conducted in Israel compared a trial treatment of a combination of CBD and THC on 60 children with ASD between the ages of five and 18 (average of 11.8) years old who suffered from such “refractory disruptive behaviors19.”
Each child was given a starting dose of plant extracts with 20:1 CBD-to-THC ratios, which were then adjusted according to each child’s reactions in the months to follow. The study itself was designed to last for 13 months, and the outcomes were measured with 4 questionnaires.
The first was a modified Liverpool Adverse Events Profile, which is generally used to measure the adverse effects of anti-epileptic medications but was included in this study because of ASD’s close relationship to epilepsy (which we will discuss more later in the article).
The second was the Caregiver Global Impression of Change (CGIC) scale, which ascertains caregivers’ insights into their patients’ global functioning. Next was the Home Situations Questionnaire-Autism Spectrum Disorder (HSQ-ASD), used to assess the severity of non-compliant behavior in children with ASD in a variety of different scenarios.
Last was the Autism Parenting Stress Index (APSI), a tool used to quantify “parenting stress specific to core and co-morbid” systems of autism.
Before we get to the results of the study, it’s important to note that 16 of the children did not complete the study—and it's important to understand that that is a relatively high “drop-out” rate. The main reasons for dropping out was either ineffectiveness of the CBD-THC or because of adverse effects. Three were treated for less than two weeks because of a marked increase in irritability or a refusal to ingest the cannabis oil, and their results are excluded from the study’s final results.
Five children stopped after between 4 and 8 months due to low efficacy, seven stopped after between 1.9 and 6.1 months due to a combination of low efficacy and adverse side effects, and one adolescent girl stopped after six months because of a psychotic event in which she refused to eat or sleep for 48 hours (though she recovered within nine days after cessation of the treatment).
As for results, the Liverpool Adverse Events Profile found that a little over half of the children suffered at least one adverse effect from the treatment, as summarized in the table below:
|Adverse Event||No. of Patients (%)|
|Any Adverse Event||29 (51%)|
|Sleep Disturbances||8 (14%)|
|Loss of Appetite||5 (9%)|
|Gastrointestinal Symptoms||4 (7%)|
|Unexplained Laughter||4 (7%)|
|Mood Changes||3 (5%)|
|Nocturnal Enuresis||2 (3.5%)|
|Gain of Appetite||2 (3.5%)|
|Weight Loss||2 (3.5%)|
|Weight Gain||2 (3.5%)|
|Dry Mouth||2 (3.5%)|
|Serious Adverse Event||No. of Patients (%)|
|Psychotic Event||1 (2%)|
On the other hand, other results from this study indicated significantly more positive results. Using the CGIC, considerable improvement in behavior problems was reported in 61% of the children, while 39% showed improvement in anxiety and 47% showed improvement in communication. HSQ-ASD scores also improved by 29%, and APSI scores improved by 33%.
This study included 18 patients with ASD, aged between 6 and 17 years old. Patients were put on a regimen of daily cannabis extracts with 75:1 CBD-to-THC ratios, with the dosing sizes adjusted on a per-patient basis within the first thirty days20.
Three patients dropped out of the treatment within this window because of adverse effects (likely due to negative interactions with other medications). One case remained with the trial for six months, while the remaining fourteen stayed on for the intended nine months. Results are based on these fifteen patients.
The success of the treatment was evaluated using a questionnaire designed by the scientists conducting the study, which asked parents to evaluate eight different symptom categories for improvement or worsening:
- Attention Deficit/Hyperactivity Disorder (ADHD)
- Behavioral Disorders (BD)
- Motor Deficits (MD)
- Autonomy Deficits (AD)
- Communication and Social Interaction Deficits (CSID)
- Cognitive Deficits
- Sleep Disorders (SD)
- Seizures (SZ)
Parents filled out the questionnaire once per month, as well as supplementary forms designed to ensure that the parents fully understood what each category evaluated. The patients’ physicians would then check the parents’ scores for consistency. If the physicians felt that the parents’ reports were inaccurate, they would recommend an adjustment to their response. It should be noted that this process may have introduced some bias into the results, however.
At the end of nine months, researchers reported mostly positive outcomes. Fourteen out of the fifteen patients had their parents report improvements of 30% or more in at least one of the evaluated criteria, and nine of these had improvements of 30% or more in multiple categories. Sleep disorders and ADHD behavior were the two most improved upon symptoms, with median improvements of 40 and 30% (respectively). What’s more, every category had a median improvement of at least 10%.
What these two studies tell us
More than anything, these two studies suggest that CBD should be taken seriously as a potential approach for ASD—and that more research into this potential is worthwhile.
Though two studies with somewhat small sample sizes are insufficient to make any claims with certainty, they are enough to justify considering CBD as a valid treatment option for people who suffer from ASD. If CBD can help ASD patients behave and sleep better while simultaneously reducing their parents’ stress levels for the few dozen families in these trials, then it is possible that others may benefit as well.
How can CBD help with ASD’s comorbid disorders?
Though ASD has far too many comorbidities to address in full here, it’s worthwhile to address at least two of the major ones: ADHD and epilepsy. As you probably noticed in the second study, ADHD was one of the symptom categories evaluated. This is because more than half of all people with ASD show signs of ADHD21, while around 15 % have diagnoses for both22.
Though little research has been conducted into the efficacy of treating ADHD with CBD, one study conducted on 30 adults with ADHD showed promising results. The active group outperformed the placebo group in both the primary and secondary outcomes of the study. These were cognitive performance and activity level, and ADHD and emotional lability symptoms, respectively.
Epilepsy, on the other hand, is the only FDA-approved disorder for cannabis treatment—which is pertinent to ASD, because between 10 and 30% of ASD patients have comorbid epilepsy. More information about the treatment of epilepsy with CBD can be found in this CBD School article.
What CBD products are best for the treatment of ASD?
All of the studies discussed in this article treated their patients with oral CBD products. Based on this limited information, we suggest trying gummies, oils, tinctures, or capsules should you consider trying CBD.
CBD and other cannabinoids are classified as food/dietary supplements, NOT as FDA-approved medications. We therefore cannot make any medical claims or give any medical advice concerning the healing powers of cannabis; we can only elucidate the available literature on the subject. We can (and do), however, encourage you to research and try cannabis-based products as you see fit. We also encourage you to speak with your medical provider prior to starting any CBD or cannabis-based regimen.
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