Investigating the Effect of Secondary Cannabis Use in Treatment Discontinuation Among Individuals Undergoing Alcohol Use Disorder Treatment

Subst Use Misuse. 2026 Mar 1:1-7. doi: 10.1080/10826084.2026.2632184. Online ahead of print.

ABSTRACT

BACKGROUND: As of 2025, medical-use cannabis is legal in 39 US states and recreational-use in 24, meaning more than half of Americans live under at least partial legalization. This shift creates new clinical considerations for individuals undergoing treatment for alcohol use disorder (AUD), particularly those who also use cannabis during treatment.

OBJECTIVE: To examine the association between cannabis co-use and completion of AUD treatment among individuals admitted primarily for alcohol-related treatment.

METHODS: We used the Substance Abuse and Mental Health Services Administration’s Treatment Episode Data Set: Discharges (TEDS-D) from 2015 to 2021. A multivariate logistic regression model estimated the association between cannabis co-use and treatment completion among patients admitted for AUD. To test robustness, the multivariate regression was repeated on a propensity score-matched subsample.

RESULTS: Cannabis co-use was associated with lower likelihood of treatment completion (odds ratio = 0.76) compared with alcohol-only patients. Treatment completion rates differed notably between alcohol-only users (74%) and those who used both alcohol and cannabis (64%). The direction and magnitude of this association remained consistent in the propensity score-matched analysis.

CONCLUSIONS: Cannabis co-use is linked with reduced treatment success among individuals treated for AUD. These findings highlight the added complexity posed by dual substance use and suggest a need for tailored interventions and clinical awareness in treatment settings.

PMID:41764413 | DOI:10.1080/10826084.2026.2632184