Exploring the Link Between Attention-Deficit Hyperactivity Disorder and Cannabis Use Disorders: A Review

Abstract

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder in children and adults. In the substance use disorders (SUDs) population, ADHD prevalence reaches 23.1%, leading to more severe substance abuse progression and reduced treatment effectiveness. Cannabis is the most common illicit drug used among the ADHD population. The increasing popularity of medical marijuana (MM) has raised concerns about its potential impact on neurocognitive functions, particularly in adolescents. Persistent cannabis use can cause permanent changes in brain structures and circuits. This review aims to overview the comorbidity of ADHD and SUDs, focusing on cannabis use disorders. Theoretical models of the etiologies of ADHD and SUDs were investigated to establish a framework for analyzing their underlying neurocognitive mechanisms. The reward and motivational brain circuitries involving the default-mode network and the endocannabinoid system were emphasized. The high prevalence of SUDs in the ADHD population has ramifications, including earlier age of onset, self-medication, and reduced performance in various domains. Cannabis use disorders are particularly significant due to the increasingly widespread use of cannabis and its perceived safety. The review highlights the lack of theoretical background on the therapeutic properties of medicinal cannabis, criticizing its speculated applications in the ADHD population. This article reviews the current understanding of the association between ADHD and cannabis use, emphasizing the need for further research and a cautious approach to MM's potential therapeutic applications.

Cannabis use and its association with psychopathological symptoms in a Swiss adult population: a cross-sectional analysis

“…Moreover, contrary to Fergusson et al, our outcomes remained significant after adjustment for other substance use as well ( 42 ). This suggests the possibility of an independent risk associated with cannabis consumption for ADHD symptom load among regular users, although the links between the two entities are complex and are beyond the scope of this paper ( 12 , 44 , 45 ). For example, a causal and temporal relationship for lifetime cannabis use was found in individuals with ADHD based on large data from genome-wide association studies with a two-sample Mendelian randomization approach.…”

“…A dose-dependent relationship was found for both hyperactive–impulsive and inattentive symptoms of ADHD with cannabis consumption ( 45 ). The co-occurrence of ADHD and CUD was discussed thoroughly in the literature ( 12 ).…”

“…While the direction of the relationship between cannabis use and non-psychotic disorders remains inconclusive, it is known that individuals with mental health disorders are more likely to use or misuse cannabis (11)(12)(13)(14).…”

Endocannabinoid System Changes throughout Life: Implications and Therapeutic Potential for Autism, ADHD, and Alzheimer’s Disease

“…These changes directly affect the release of neurotransmitters, such as dopamine and norepinephrine. Of special interest, the ECS has been linked to dopamine production, suggesting a connection between endocannabinoids and ADHD [ 65 ].…”

“…According to what has been previously mentioned, changes in different components of the ECS can contribute to a variety of neurological disorders, primarily due to differences in the gene and protein expression of CB1R. Indeed, a high concentration of CB1R is found in areas associated with cognitive processing and functioning; it also plays a crucial role in regulating the release of monoamines [ 65 ]. Importantly, decreased CB1R gene and protein expression was found in the brainstem [ 66 ].…”