IntroductionRacial/ethnic discrimination (hereafter, discrimination) is associated with use of individual tobacco and cannabis products. However, we know little about how discrimination affects dual/polytobacco and cannabis use and associated use disorders. MethodsWe used cross-sectional data on adults (18+) from the 2012–2013 National Epidemiologic Survey on Alcohol and Related Conditions-III (n = 35,744). We defined past-year discrimination as a summary scale (range: 0–24) based on six scenarios. We created a mutually exclusive six-category use variable: noncurrent, individual tobacco and noncannabis, individual tobacco and cannabis, individual cannabis and nontobacco, dual/polytobacco and noncannabis, and dual/polytobacco and cannabis based on past 30-day tobacco use of four products (i.e., cigarettes, electronic nicotine delivery systems, other combustibles (cigars, pipe), smokeless tobacco) and cannabis use. We also examined past-year tobacco use disorder (TUD) and cannabis use disorder (CUD) as a four-level variable: no disorders, TUD only, CUD only, and TUD and CUD. We estimated associations between discrimination and each outcome using adjusted multinomial logistic regression and assessed effect modification by stratifying adjusted models by race/ethnicity (i.e., Hispanic, non-Hispanic (NH) White, NH Black, and another race/ethnicity). ResultsExperiencing more discrimination was associated with each outcome but was most strongly associated with dual/polytobacco and cannabis use (OR: 1.13, 95 % CI: 1.07–1.19) and joint TUD and CUD (OR: 1.16, 95 % CI: 1.12–1.20). Models stratified by race/ethnicity showed that discrimination was associated with dual/polytobacco and cannabis only among NH White adults, and with joint TUD and CUD only among NH Black and NH White adults. ConclusionsDiscrimination was associated with tobacco and cannabis use outcomes among multiple adult racial/ethnic populations, but associations were more profound for NH White and NH Black adults than adults from other racial/ethnic populations.