Quantification of Flualprazolam in Blood by LC–MS-MS: A Case Series of Nine Deaths

The emergence of novel designer benzodiazepines continues to be a public health concern. Flualprazolam is one of these drugs. It was initially identified in 2017. User forums suggest it is slightly more potent than alprazolam and has longer-lasting central nervous system depressant effects. Here we report a simple, sensitive liquid chromatography-tandem mass spectrometry method for flualprazolam and report a series of nine cases in which flualprazolam was quantified. As is typical of forensic toxicology in the twenty-first century, all the cases had more than one drug present. None of the deaths could be directly attributed to flualprazolam alone, but all were likely due to a combination of sedative drugs. However, this paper still adds to the data available to allow interpretation of postmortem flualprazolam concentrations.