Systematic review finds cannabinoids may improve behavioral symptoms and sleep in people with autism | Research

The takeaway

A systematic review of 10 studies found cannabinoids, primarily CBD-rich preparations, appeared to improve problem behaviors, sleep, and hyperactivity in people with autism, while also reducing seizures in those with comorbid epilepsy.

Families of individuals with autism, ASD researchers, and clinicians exploring adjunctive treatments.

Cannabinoids improved behavioral symptoms and reduced medication burden

What the researchers found

Cannabinoids improved some autism-associated symptoms including problem behaviors, sleep problems, and hyperactivity, with limited side effects. They also reduced medication burden and seizure frequency in patients with comorbid epilepsy. Evidence on core ASD symptoms (social communication, repetitive behaviors) remained scarce.

Why it matters

Autism spectrum disorder has limited treatment options, particularly for associated behavioral symptoms. These preliminary findings suggest cannabinoids could address comorbid symptoms and reduce polypharmacy.

The numbers in context

10 published studies reviewed plus 4 ongoing trials identified. Most studies used CBD-dominant preparations. Side effects were primarily cardiac and metabolic, described as limited.

How the study worked

Systematic review following PRISMA guidelines, searching Web of Knowledge, PsycINFO, and Embase. Ten studies (8 papers, 2 abstracts) were included, plus 4 ongoing trials from ClinicalTrials.gov.

What this study cannot tell us

Most included studies were observational with small samples and no control groups. Heterogeneous study designs, cannabis preparations, and outcome measures make comparison difficult.

How to read the evidence

Moderate: systematic review methodology, but most included studies were small and observational.

When this study was published

Published in 2020 in Brain Sciences.

The bigger picture

While findings are promising for secondary symptoms, the lack of evidence on core ASD symptoms means cannabinoids currently appear more useful as adjunctive treatment for comorbid conditions rather than as a primary autism treatment.

Questions still open

Will the four ongoing RCTs confirm these preliminary findings? Can cannabinoids address core ASD symptoms or only associated behaviors? What is the optimal CBD formulation and dose for ASD?

Common questions

Can CBD treat autism?

There is no evidence that CBD treats the core features of autism (social communication difficulties, repetitive behaviors). However, preliminary studies suggest it may help with associated symptoms like problem behaviors, sleep difficulties, and hyperactivity.

What about the connection to epilepsy?

About 20-30% of people with ASD also have epilepsy, and the two conditions share some biological mechanisms involving GABA. In studies where patients had both conditions, cannabinoids appeared to reduce seizure frequency, consistent with CBD's established anti-seizure properties.

Read the original research

Cannabinoids for People with ASD: A Systematic Review of Published and Ongoing Studies.

Brain sciences, 10(9)

View on PubMed ↗Publisher’s paper ↗

Citation

Fusar-Poli, Laura; Cavone, Vito; Tinacci, Silvia; Concas, Ilaria; Petralia, Antonino; Signorelli, Maria Salvina; Díaz-Caneja, Covadonga M; Aguglia, Eugenio. (2020). Cannabinoids for People with ASD: A Systematic Review of Published and Ongoing Studies.. Brain sciences, 10(9). https://doi.org/10.3390/brainsci10090572