14 Surveillance of a Top Trending Designer Benzodiazepine at an Academic Medical System

As the field of novel psychoactive substances (NPS) has expanded, designer benzodiazepines (DBZDs) have become a significant drug class. One of the challenges in detecting NPS drugs is that the chemical structure is constantly modified, likely in an attempt to avoid legal sanctions. Historically, there have been multiple different compounds circulating within the drug class DBZDs, making it difficult for clinical laboratories to develop assays for detection. Since the end of 2022, a single drug known as bromazolam has emerged as the primary DBZD being detected. In this work, we investigated the cross-reactivity of bromazolam in the urine benzodiazepine screen and to evaluate clinical patient urines submitted for urine drug testing for the presence of bromazolam. Initial evaluation of bromazolam included determining cross-reactivity of the drug in urine benzodiazepine screens. Two immunoassays were evaluated, the Abbott Alinity c Benzodiazepines screen and the Emit II Plus Benzodiazepine assay, by spiking drug screen negative urine with bromazolam. The lowest concentration of bromazolam that screened positive for both assays was 200 ng/mL. To evaluate the clinical prevalence of the drug, patient urines were evaluated during the time frame of October to December 2024. Samples were selected for bromazolam confirmation testing if the urine screened positive in one of the following urine drug screens: benzodiazepines, fentanyl, cocaine, amphetamines or PCP. A qualitative confirmation method was developed using liquid chromatography tandem mass spectrometry (LC-MSMS) with multiple reaction monitoring to identify the presence of bromazolam. The evaluation of patient urine identified bromazolam in 36 urine samples over a time period of 3 months. Of these 36 samples, 20 (56%) screened positive by the benzodiazepine drug screen and of these, 4 urines were co-positive with other benzodiazepines. Other drugs detected in the urine samples were also evaluated, and the highest co-positivity was observed with fentanyl (86%), followed by cocaine (75%) and methamphetamine/amphetamine (47%). Additionally, 33 patients had at least two co-positive drug classes, and notably, bromazolam was never detected in isolation. While the urine benzodiazepine screen was able to detect bromazolam during a spiking study, evaluation of clinical patient urines showed that an LC-MSMS approach was more sensitive for detecting bromazolam. Preliminary testing showed that bromazolam is often present with other drugs typically included in a urine drug screen.