ADHD News & Research

Almost Half of People with Cannabis Use Disorder Have ADHD

Frequent, problematic cannabis use is more common among individuals with ADHD, who also discount or downplay the risks associated with cannabis use, according to a new systematic review.

July 17, 2023

Nearly half of people with cannabis use disorders also have attention deficit hyperactivity disorder (ADHD)1, according to a new systematic review that also found almost a quarter (23%) of people with substance use disorders have ADHD.2

Researchers found a positive relationship between severity of ADHD symptoms and likelihood of continued, increasing cannabis use and development of cannabis use disorder (CUD). They uncovered a host of structural changes that occur in the brains of young people who regularly use cannabis, however they also found a prevailing belief among many people with ADHD that the risk associated with cannabis use is low, and the benefits are high, particularly for the improvement of sleep disturbance, social anxiety, and executive functioning. The researchers said more study is needed to assess the accuracy of this belief, however some experts argue that the risks of cannabis use by individuals with ADHD are well founded.

“Tetrahydrocannabinol (THC), one of cannabis’ active compounds, inhibits neuronal connections and effectively slows the brain’s signaling process. THC also affects the brain’s dendrite architecture, which controls processing, learning, and the overall health of the brain,” said Roberto Olivardia, Ph.D., in a recent ADDitude webinar entitled Marijuana and the ADHD Brain: How to Identify and Treat Cannabis Use Disorder in Teens and Young Adults. “People with ADHD, whose brain development is delayed by slowly maturing frontal lobes, are thus more vulnerable to cannabis’ effects on neuronal connections. Some of these impairments may be irreversible.”

Regular Cannabis Use Causes Structural Brain Changes

Regular use of cannabis causes a host of structural changes in the brains of young people with ADHD, according to the review. These changes include:

  • lessened dopamine transporter availability
  • increased activation of the right hippocampus and cerebellar vermis
  • narrower caudal inferior frontal gyrus
  • thinner cortical layers in the right precentral and postcentral gyri

Perception of Cannabis As Low-Risk

There is a prevailing belief among populations with ADHD that marijuana is a low-risk substance, less dangerous than other drugs. It is also generally believed by those who use it to be beneficial for the management of ADHD symptoms. The review concluded that, while there is no evidence or clinical guidelines that support this widespread belief, it is a possible driver of cannabis use in people with ADHD.3

“Cannabis activates the brain’s reward system, and releases dopamine at levels higher than typically observed. In low-dopamine ADHD brains, THC thus can be very rewarding,” Olivardia explained. “Also contributing to an increased likelihood of cannabis use and (CUD) among individuals with ADHD is the prevalence of low self-esteem, sleep problems, poor impulse control, and sensation-seeking tendencies in this population.”

Cannabis Used to Cope with ADHD Symptoms

The review revealed that people with ADHD frequently used cannabis to manage problematic symptoms, such as social anxiety and sleep disturbances.

“Marijuana helps my comorbid anxiety; it makes it impossible to ruminate on anything,” shared one ADDitude reader in a recent survey. “However. precisely because of its ’forgetting effect,’ it exacerbates my inattentive symptoms.”

Many individuals point to sleep disturbances caused by ADHD (or in some cases, ADHD medication), as a reason for cannabis use. The systematic review found that, while cannabis may provide short-term benefits for sleep, patients grow accustomed to these benefits, which encourages increased use and raises the risk of cannabis-related problems.4

David, an ADDitude reader, experienced this phenomenon first-hand: “I used edibles for about three years, initially as a way to sleep,” he explained. “But once I got used to the marijuana, my brain woke up, and every night, I felt like I was trapped by these waves of negative thoughts before bed.”

This complicated calculus, in which short-term benefits are weighed against long-term costs, is borne out by research. The authors of a recent study on self-reported effects of cannabis on ADHD symptoms concluded: “People using cannabis to self-medicate for symptoms of mental disorders may experience immediate relief when acutely intoxicated because the drug masks these symptoms. However, cannabis doesn’t address the root core issues underlying the problems. As such, when the effects of the drug wear off, the symptoms return, leading them to need to use the drug more frequently, which increases the risk of developing CUD.”5

“Prolonged, excessive use of cannabis causes me significant anxiety and depression so there are times when I will lower my dose, but it always goes back up eventually,” says Suzanne, an ADDitude reader in Winnipeg. “However, my overall life functioning (work and personal) has very much improved since taking cannabis regularly.”

While the review sheds light on many aspects of a complex relationship, the review’s authors said the benefits and detriments of cannabis use for people with ADHD require more study.

View Article Sources

1Notzon DP, Pavlicova M, Glass A, Mariani JJ, Mahony AL, Brooks DJ, Levin FR: ADHD Is highly prevalent in patients seeking treatment for cannabis use disorders. J Atten Disord. 2020, 24:1487-92. 10.1177/1087054716640109

2Elkins IJ, Saunders GR, Malone SM, Keyes MA, McGue M, Iacono WG: Associations between childhood ADHD, gender, and adolescent alcohol and marijuana involvement: a causally informative design. Drug Alcohol Depend. 2018, 184:33-41. 10.1016/j.drugalcdep.2017.11.011

3Metrik J, Bassett SS, Aston ER, Jackson KM, Borsari B: Medicinal versus recreational cannabis use among returning veterans. Transl Issues Psychol Sci. 2018, 4:6-20. 10.1037/tps0000133

4Babson KA, Sottile J, Morabito D: Cannabis, cannabinoids, and sleep: a review of the literature. Curr Psychiatry Rep. 2017, 19:23. 10.1007/s11920-017-0775-9

5Stueber, A., & Cuttler, C. (2021). Self-Reported Effects of Cannabis on ADHD Symptoms, ADHD Medication Side Effects, and ADHD-Related Executive Dysfunction. Journal of Attention Disorders.