Adolescent substance use commonly co-occurs with poor mental health, bullying victimization and risky behaviors that may lead to violence. The purpose was to describe the United States (US) national prevalence of polysubstance use and co-occurring characteristics and associated demographic characteristics among youth. Middle and high school students in the 2019 CDC YRBS survey reported their demographics and current ( ≥ 1 days in the last 30 days) substances used (alcohol, cigarette, e-cigarette, cannabis)
polysubstance combinations were generated. Cross-sectional weighted logistic regression estimated odds of polysubstance use and frequent use ( ≥ 6 days in the last 30 days) by weapon carrying, depressive symptoms, bullying victimization, and demographics. Mean age of the sample was 16 years, 51% were boys, 51% were non-Hispanic White. While accounting for 21% of the sample, 22-40% of Multiracial youth reported polysubstance use and frequent use. Odds of frequent polysubstance use (all combinations) were highest for weapon carrying youth.