CANNABIS USE IN ADOLESCENTS WITH ADHD: IMPACT ON SYMPTOMS AND EXECUTIVE FUNCTION

Abstract

Adolescents with attention-deficit/hyperactivity disorder (ADHD) have an elevated risk of early substance use and cannabis use disorder, while cannabis is frequently perceived as calming, sleep-promoting, or therapeutic. This narrative review examines whether cannabis improves ADHD symptoms and how use relates to attention, inhibition, working memory, planning, motivation, and everyday executive function. The evidence does not support cannabis as a treatment for ADHD. Acute tetrahydrocannabinol exposure impairs attention, learning, memory, reaction time, and inhibitory control; frequent adolescent use is associated with small-to-moderate cognitive disadvantages, although effect sizes, persistence, and causality vary across studies. Evidence specific to young people with ADHD is sparse. A systematic review found no consistent additive ADHD-by-cannabis deficit on neuropsychological tests, but the included studies were few, heterogeneous, and often underpowered; absence of a detected interaction should not be interpreted as safety. Cross-sectional comparisons are strongly confounded because executive dysfunction, impulsivity, conduct problems, family risk, sleep disturbance, and school disengagement can precede cannabis initiation. Longitudinal and co-twin studies indicate that both selection effects and exposure-related change contribute, with earlier onset, frequent use, high-potency products, and cannabis use disorder representing greater concern. Several abstinence studies demonstrate at least partial recovery of memory or executive performance over weeks. Clinically, assessment should separate intoxication, withdrawal, persistent ADHD, sleep problems, mood symptoms, and learning difficulties; quantify product, tetrahydrocannabinol content, route, frequency, and functional consequences; and screen confidentially for cannabis use disorder and safety risks. Evidence-based ADHD treatment should continue when indicated, with diversion precautions, motivational interviewing, family-supported behavioral care, cognitive-behavioral treatment for cannabis use disorder, and contingency management. Cannabis should not be recommended to manage ADHD symptoms in adolescents.