There are major international studies investigating cannabis as a treatment option for symptoms of ASD.
Editor’s Note: This article has been archived 06/06/2019.
The results of the study are not yet complete 02/07/2020.
Autism Spectrum Disorder (ASD) is an umbrella term to describe a collection of disorders that are primarily characterized by difficulties with social interactions and language development. These disorders become apparent at a young age, and are often accompanied by behavioral issues.
The deficiencies in social interaction skills and awareness make it difficult for children with autism to control their own emotions and to identify with the emotions of others. They tend to avoid eye contact, for example. Those with autism also tend to have very specific and restricted interests.
The cause of ASD is not currently known, and indeed, there are likely multiple factors at play. Some genetic mutations common to ASD patients have been identified, and many of the affected genes are responsible for brain development and synapse function. There are also a number of environmental risk factors that have been identified.
The treatments of ASD are limited and largely based on behavioral therapies. There are some medications that have been prescribed, including antidepressants and antipsychotics, but these often come with difficult side effects. As a result, an increasing number of parents of children with ASD are wondering if cannabis could be a viable treatment option.
Currently, there is no published scientific or clinical data obtained from children with ASD that indicate cannabis could effectively treat the disorder or its symptoms. But, this could change over the next several years. There is one clinical trial on the effects of cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) in a ratio of 20:1 on the behavioral problems in children with ASD.
This study opened for recruitment in January 2017 and will close in 2019, so no data will be available until that time. In addition, there are several other organizations world-wide that are likely to begin clinical trials in 2018, including Zelda Therapeutics in Chile and Lehigh University in Pennsylvania, USA.
The anecdotal evidence and data obtained from small case studies does hold promise for the use of cannabis in ASD, however. There have been a small number of case studies, some involving just one patient, that demonstrated improvements in behavior after cannabis use or taking a synthetic version of THC. Zelda Therapeutics performed an observational study using cannabis on 21 patients in Chile that showed promising results in the improvement of social interaction and repetitive behaviors, although this data has not been published.
Studies of all kinds of behavioral and psychiatric disorders have found that the endocannabinoid system is involved in functions like mood regulation, social functioning, and overcoming anxiety. This has motivated scientists to look for changes in the endocannabinoid system of ASD patients in order to learn more about the causes of ASD and whether cannabis could be therapeutic. Several studies have found higher levels of cannabinoid receptor CB2 in the immune cells of patients with ASD, indicating that the endocannabinoid system is involved in the immune system dysfunction that some ASD patients experience.
Animal models of the various behaviors and symptoms of ASD have also been used to explore the role of the endocannabinoid system in autism. One study on mice found that the genetic mutations to the neurologin 3 protein (NL3) associated with autism disrupts endocannabinoid signaling in the brain. NL3 is a cell-adhesion protein found in neural synapses, and the mutations appeared to prevent the cannabinoid receptor CB1, also present in the synapse, from regulating signaling between neurons.
Another mouse study found that the endocannabinoid system was involved in the development of communication; mice with no CB1 receptor had lower levels of communication, which corresponds to the kind of communication impairment in children with ASD. Other studies have shown that the endocannabinoid system is involved in regulating the behavioral issues like social interactions and repetitive activity.
While some of the animal studies and preclinical data from ASD patients are encouraging, parents should be extremely cautious in the use of cannabis to treat autism. Children’s brains are still undergoing significant development, and the endocannabinoid system plays a role in brain development. Overstimulating the endocannabinoid system and disrupting this development could have repercussions.
The research has shown that regular adolescent use or abuse of cannabis can cause psychiatric side effects in adulthood, including decline of IQ and increased risk of developing schizophrenia and anxiety disorders. This has been found to be exacerbated in those with pre-existing neurological conditions. We can be sure, however, that parents of children with ASD will be anxiously awaiting the results of clinical trials that are currently underway.