In recent years, a growing number of people with autism, and their families, have looked to test the potential of cannabis and its derivatives for the improvement of autism-related traits and behaviours. Many are looking to find an alternative to more commonly used medications and therapies.
While anecdotal evidence on the subject is freely available through sources such as internet forums, social media, and word of mouth, there remains a lack of clinical research into the safety and efficacy of cannabis for autism and related conditions.
The growing use of medical cannabis
While we have been using cannabis for medicinal, spiritual, and industrial purposes for thousands of years, our relationship with the plant became significantly thwarted over the last century, with the majority of countries around the world imposing a strict prohibition on the crop. However, research into – and access to – cannabis has gradually increased in more recent years, with a significant number of countries developing legal channels to access medical cannabis.
Research has shown that the various compounds found within the plant – particularly cannabinoids like CBD and THC – can be useful in the treatment and management of a number of conditions, including epilepsy, chronic pain, multiple sclerosis, and cancer. But how could these products potentially help people with autism to manage their condition?
What is Autism?
Autism Spectrum Disorder (ASD) is a neurodevelopment condition that is characterised by an impairment in three domains: social interaction, communication, and behaviour patterns. Autism can range significantly in severity and symptom types – prompting the name ‘spectrum disorder’.
Symptoms and behaviours associated with ASD usually appear at an early age, however, diagnosis can be confirmed at any age. According to the World Health Organisation, around 1 in 160 children around the world has an ASD, with boys being between three and four times more likely to be diagnosed than girls.
While the causes of autism are not fully understood, it is believed to be linked to a number of both genetic and environmental factors. Autism is often also associated with other conditions, including Fragile X, Rett syndrome, tuberous sclerosis, and phenylketonuria. Around 20-25% of individuals with autism are also diagnosed with epilepsy at some point in their lives.
Existing Evidence
There are currently no medications that address the core symptoms of autism. Existing medications are employed to target comorbid symptoms such as anxiety or mood symptoms and aggressive behaviour. However, these options often have questionable efficacy and can be associated with a number of side effects.
There is growing anecdotal evidence supporting the use of cannabis products – including CBD – as an alternative treatment. In the US, medical cannabis has been available on prescription in 14 states since 2014. However, there remains little clinical research in this area.
A recent double-blind, randomised controlled trial was carried out to assess the efficacy of two oral cannabinoid solutions for participants with autism spectrum disorder (ASD). The study aimed to build on existing evidence of endocannabinoid dysfunction in animal models of ASD and anecdotal evidence for the efficacy of medical cannabis in humans.
On analysis of CGI-I reports, 49% of 45 participants who received the whole-plant cannabinoid preparation (20:1 CBD vs THC) positively responded (either much or very much improved) in comparison to 21% of 47 treated with placebo. This study demonstrated, for the first time in a placebo-controlled trial, that cannabinoid treatment has the potential to decrease disruptive behaviours often associated with ASD as assessed by a subjective scoring assessment.
Anecdotal Evidence
Anecdotal reports from people with autism and their families suggest that cannabis consumption may help to improve some symptoms of ASD. Some reports show that cannabis use may particularly aid in the enhancement of interpersonal communication and decrease hostile feelings.
As the likelihood of developing forms of epilepsy is particularly high in populations with autism, medical cannabis may also be of interest for another reason. There is growing evidence that cannabinoids – most commonly CBD and THC – can be effective at reducing seizure severity and frequency in treatment-resistant forms of epilepsy.
GW Pharmaceuticals – the manufacturer of CBD-based medicinal cannabis product Epidyolex – is now also conducting trials for Rett syndrome – a neurodevelopmental condition related to autism with a focus on improving cognitive and behavioural problems associated with the condition.
The company is also currently recruiting children and teenagers to take part in a phase 2 trial of cannabidivarin (a minor cannabinoid) to determine its effects on a number of factors associated with autism.
