Cannabinoids in attention-deficit/hyperactivity disorder: A randomised-controlled trial.



Adults with ADHD describe self-medicating with cannabis, with some reporting a preference for cannabis over ADHD medications. A small number of psychiatrists in the US prescribe cannabis medication for ADHD, despite there being no evidence from randomised controlled studies. The EMA-C trial (Experimental Medicine in ADHD-Cannabinoids) was a pilot randomised placebo-controlled experimental study of a cannabinoid medication, Sativex Oromucosal Spray, in 30 adults with ADHD. The primary outcome was cognitive performance and activity level using the QbTest. Secondary outcomes included ADHD and emotional lability (EL) symptoms. From 17.07.14 to 18.06.15, 30 participants were randomly assigned to the active (n=15) or placebo (n=15) group. For the primary outcome, no significant difference was found in the ITT analysis although the overall pattern of scores was such that the active group usually had scores that were better than the placebo group (Est=-0.17, 95%CI-0.40 to 0.07, p=0.16, n=15/11 active/placebo). For secondary outcomes Sativex was associated with a nominally significant improvement in hyperactivity/impulsivity (p=0.03) and a cognitive measure of inhibition (p=0.05), and a trend towards improvement for inattention (p=0.10) and EL (p=0.11). Per-protocol effects were higher. Results did not meet significance following adjustment for multiple testing. One serious (muscular seizures/spasms) and three mild adverse events occurred in the active group and one serious (cardiovascular problems) adverse event in the placebo group. Adults with ADHD may represent a subgroup of individuals who experience a reduction of symptoms and no cognitive impairments following cannabinoid use. While not definitive, this study provides preliminary evidence supporting the self-medication theory of cannabis use in ADHD and the need for further studies of the endocannabinoid system in ADHD.


Ruth E. Cooper, Emma Williams, Seth Seegobin, Charlotte Tye, Jonna Kuntsi, Philip Asherson

Published in European Neuropsychopharmacology

August 2017


DOI: 10.1016/j.euroneuro.2017.05.005



Cooper RE, Williams E, Seegobin S, Tye C, Kuntsi J, Asherson P. Cannabinoids in attention-deficit/hyperactivity disorder: A randomised-controlled trial. European Neuropsychopharmacology. 2017;27(8):795-808. doi:10.1016/j.euroneuro.2017.05.005.

The impact of ADHD persistence, recent cannabis use, and age of regular cannabis use onset on subcortical volume and cortical thickness in young adults.



Krista M. Lisdahl, Leanne Tamm, Jeffery N. Epstein, Terry Jernigan, Brooke S. G. Molina, Stephen P. Hinshaw, James M. Swanson, Erik Newman, Clare Kelly, James M. Bjork, MTA Neuroimaging Group

Published in Drug and Alcohol Dependence

1 April 2016




Both Attention Deficit Hyperactivity Disorder (ADHD) and chronic cannabis (CAN) use have been associated with brain structural abnormalities, although little is known about the effects of both in young adults.


Participants included: those with a childhood diagnosis of ADHD who were CAN users (ADHD_CAN; n=37) and non-users (NU) (ADHD_NU; n=44) and a local normative comparison group (LNCG) who did (LNCG_CAN; n=18) and did not (LNCG_NU; n=21) use CAN regularly. Multiple regressions and MANCOVAs were used to examine the independent and interactive effects of a childhood ADHD diagnosis and CAN group status and age of onset (CUO) on subcortical volumes and cortical thickness.


After controlling for age, gender, total brain volume, nicotine use, and past-year binge drinking, childhood ADHD diagnosis did not predict brain structure; however, persistence of ADHD was associated with smaller left precentral/postcentral cortical thickness. Compared to all non-users, CAN users had decreased cortical thickness in right hemisphere superior frontal sulcus, anterior cingulate, and isthmus of cingulate gyrus regions and left hemisphere superior frontal sulcus and precentral gyrus regions. Early cannabis use age of onset (CUO) in those with ADHD predicted greater right hemisphere superior frontal and postcentral cortical thickness.


Young adults with persistent ADHD demonstrated brain structure abnormalities in regions underlying motor control, working memory and inhibitory control. Further, CAN use was linked with abnormal brain structure in regions with high concentrations of cannabinoid receptors. Additional large-scale longitudinal studies are needed to clarify how substance use impacts neurodevelopment in youth with and without ADHD.


DOI: 10.1016/j.drugalcdep.2016.01.032

Author Manuscript


Lisdahl KM, Tamm L, Epstein JN, et al. The impact of ADHD persistence, recent cannabis use, and age of regular cannabis use onset on subcortical volume and cortical thickness in young adults. Drug and Alcohol Dependence. 2016;161:135-146. doi:10.1016/j.drugalcdep.2016.01.032.

Association of the cannabinoid receptor gene (CNR1) with ADHD and post‐traumatic stress disorder.



Ake T. Lu, Matthew N. Ogdie, Marjo‐Ritta Järvelin, Irma K. Moilanen, Sandra K. Loo James T. McCracken, James J. McGough, May H. Yang, Leena Peltonen, Stanley F. Nelson Rita M. Cantor, Susan L. Smalley

Published in American Journal of Medical Genetics Part B: Neuropsychiatric Genetics

22 January 2008



Attention deficit hyperactivity disorder (ADHD) is a highly heritable disorder affecting some 5-10% of children and 4-5% of adults. The cannabinoid receptor gene (CNR1) is a positional candidate gene due to its location near an identified ADHD linkage peak on chromosome 6, its role in stress and dopamine regulation, its association with other psychiatric disorders that co-occur with ADHD, and its function in learning and memory. We tested SNP variants at the CNR1 gene in two independent samples-an unselected adolescent sample from Northern Finland, and a family-based sample of trios (an ADHD child and their parents). In addition to using the trios for association study, the parents (with and without ADHD) were used as an additional case/control sample of adults for association tests. ADHD and its co-morbid psychiatric disorders were examined. A significant association was detected for a SNP haplotype (C-G) with ADHD (P = 0.008). A sex by genotype interaction was observed as well with this haplotype posing a greater risk in males than females. An association of an alternative SNP haplotype in this gene was found for post-traumatic stress disorder (PTSD) (P = 0.04 for C-A, and P = 0.01 for C-G). These observations require replication, however, they suggest that the CNR1 gene may be a risk factor for ADHD and possibly PTSD, and that this gene warrants further investigation for a role in neuropsychiatric disorders.


DOI: 10.1002/ajmg.b.30693

Full Text


Lu AT, Ogdie MN, Järvelin M-R, et al. Association of the cannabinoid receptor gene (CNR1) with ADHD and post-traumatic stress disorder. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics. 2008;147B(8):1488-1494. doi:10.1002/ajmg.b.30693.

Treating Adult ADHD with Cannabis

By | ADHD, Research Articles

Treating Adult ADHD with CannabisThe medical certificates of 30 patients with adult ADHD, who were granted approval by the German Health Ministry to use cannabis flowers between 2012 and 2014, were analysed with regard to course of disease, previous treatment efforts, and effects of self-medication with cannabis or therapy with cannabis-based medications. For adult patients with ADHD, who experience side effects or do not profit from standard medication, cannabis may be an effective and well-tolerated alternative. Read More