A quarterly publication of the Autism Research Institute

The Autism Research Review International is quarterly publication of the Autism Research Institute

Winter, 2021 | Number 1, Volume 35

Cannabinoid treatment may reduce behavior problems in children, teens with ASD

Treatment with cannabinoids (compounds found in marijuana) may help to reduce behavior problems in young individuals with autism spectrum disorders (ASD), according to a new study from researchers in Israel and the United States. 

In the double-blind, placebo-controlled study, Adi Aran and colleagues tested the effects of a whole-plant cannabis extract and pure cannabinoids on 150 children and adolescents with ASD. Two-thirds of the participants received cannabinoids for 12 weeks (half received the whole-plant extract and half received the purified cannabinoids) while the other third received a placebo. After a four-week washout period, participants were moved to different groups. (Due to a treatment order effect that could impair the validity of their findings, the researchers evaluated efficacy during the first period but not the second. However, data on safety and tolerability were measured in both phases.) 

The researchers report that scores on the Clinical Global Impression-Improvement Scale showed that disruptive behavior was either much or very much improved in 49% of participants receiving the whole-plant extract versus only 21% of participants receiving the placebo. In addition, scores on the Social Responsiveness Scale indicated that cannabinoid treatment improved ASD core symptoms. The only common side effects were sleepiness and decreased appetite. 

Aran and colleagues say, “Currently, there are no established medications for the core autistic symptoms. Risperidone and aripiprazole have been approved by the U.S. Food and Drug Administration to treat comorbid irritability but these medications often cause obesity and metabolic syndrome. In this study, we have demonstrated for the first time in a placebo-controlled trial that cannabinoid treatment has the potential to decrease disruptive behaviors associated with ASD, with acceptable tolerability. This is specifically important for the many individuals with ASD who are overweight, as cannabinoid treatment was associated with net weight loss in contrast to the substantial weight gain usually produced by antipsychotics.” 

The researchers note, however, that caution is warranted in interpreting their results due to the study participants’ wide range of ages and functional levels.


“Cannabinoid treatment for autism: a proof-ofconcept randomized trial,” Adi Aran, Moria Harel, Hanoch Cassuto, Lola Polyansky, Aviad Schnapp, Nadia Wattad, Dorit Shmueli, Daphna Golan, and F. Xavier Castellanos, Molecular Autism, February 2021 (free online). Address: Adi Aran, Neuropediatric Unit, Shaare Zedek Medical Center, 12 Bayit Street, 91031 Jerusalem, Israel, [email protected].