The legalisation of recreational cannabis in US states has not led to a statistically significant increase in hospital admissions for cannabis use disorder amongst teenagers, according to a comprehensive study published in the International Journal of Drug Policy.
Researchers analysed 2,861,324 inpatient discharge records for adolescents aged 10-17 across 13 US states between 2008 and 2020, examining whether state cannabis legalisation affected the prevalence of cannabis use disorder (CUD) diagnoses in hospital settings.
Cannabis use disorder is diagnosed in patients who meet at least two of the 11 criteria required by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition. The condition is defined by persistent cannabis use despite clinically significant impairment.
The researchers used quasi-experimental designs that accounted for staggered policy adoption across different states, examining both the immediate and longer-term effects of legalisation on adolescent hospitalisations involving CUD diagnoses.
“This multi-state analysis of adolescent inpatient encounters across 13 US states between 2008 and 2020 found no consistent evidence that state nonmedical cannabis legalization was associated with an increase in the prevalence of CUD diagnoses among adolescents,” the study’s authors said. “Across multiple models and demographic subgroups, the analysis consistently found a null association, suggesting that the prevalence of this clinical diagnosis remained stable following major policy shifts.”
The findings remained consistent across different demographic groups, including variations by sex, age, race and ethnicity, and urban versus rural locations. The researchers also conducted sensitivity analyses using dispensary opening dates as an alternative measure, which produced similar results.
The study adds to a growing body of evidence dismissing the fear that adult-use legalisation leads to increased cannabis use amongst teenagers.
Recent data from Germany showed that youth cannabis use amongst teenagers aged 12-17 declined after adult-use legalisation in April 2024. According to the Federal Institute for Public Health’s “Drug Affinity Study 2025,” which surveyed 7,001 young people between April and July 2025, past-year consumption fell from 6.7% to 6.1%, while regular use dropped from 1.3% to 1.1%. Former health minister Karl Lauterbach stated the results aligned with legalisation goals, emphasising youth protection through public debate on cannabis risks.
According to previous research in the US, data consistently show that licensed cannabis retailers are more likely than alcohol retailers to deny entry to those without proper identification. Since 2015, state regulators have conducted over 7,800 compliance checks of licensed cannabis establishments. In over 94 per cent of cases, minors were denied cannabis access.
“Regulation works,” NORML’s Deputy Director Paul Armentano said. “Illicit marijuana providers don’t ask for or check for ID, but licensed businesses most certainly do. States’ real-world experience with adult-use marijuana legalization affirms that it is being implemented in a way that provides regulated access for adults while simultaneously limiting youth access and misuse.”
