Mistaken Identity: A Prevalence Study of Bromazolam in the American Great Lakes Region

BACKGROUND: Bromazolam (BRZ) is a novel psychoactive substance benzodiazepine drug that has recently emerged within the illicit drug supply in the United States. BRZ is not FDA-approved and is distributed in drug mixtures or as counterfeit "Xanax". We explored the BRZ prevalence from oral fluid samples submitted to our lab for testing. METHODS: BRZ-positive sample results were examined between August 2024 and November 2025. Illicit drug and other benzodiazepine content, medication lists, and associated county data were also gathered to indicate prevalence, identify use trends, and map BRZ use. RESULTS: BRZ was found in 219 of 4,579 samples that screened positive for benzodiazepines (4.8%). Approximately half (109, 49.8%) of cases contained at least one illicit substance. A subset of samples (45, 20.5%) listed at least one prescription benzodiazepine; many of these samples reported negative for the listed medication (17, 37.8%). BRZ use was widespread in the Great Lakes region, but declined in prevalence over time. CONCLUSIONS: BRZ was found with illicit drugs as well as by itself, presenting a challenge in clinical settings relying on instant screening devices for benzodiazepine compliance. The observed decline in BRZ use may indicate a possible shift in drug use trends.