Prevalence of N,N-Dimethylpentylone in forensic toxicology casework: A retrospective study and trends in the state of Florida.

Substituted cathinones (SCs) have been more prominent in the state of Florida than in many other jurisdictions across the United States. Since mid-2021, N,N-Dimethylpentylone (DMP) has been the most encountered cathinone in forensic casework, though its prevalence has varied across the state. Given this prevalence and variability, developing a more comprehensive understanding of DMP became increasingly important. The aim of this study was to assess the prevalence of DMP in Florida from late 2021 through 2024 and to characterize its pharmacologic and toxicologic effects observed in authentic cases. A total of 844 cases from four forensic toxicology laboratories in Florida were positive for DMP, including 760 postmortem investigations, 42 driving under the influence of drugs cases, and 42 drug-facilitated crime cases. Beginning in 2021 Q4, a steady increase in DMP identifications was observed, with the highest number of detections noted in 2023 Q3 (n = 101). Among the agencies in this study, the majority of DMP positivity was observed in postmortem cases, most often in conjunction with cocaine and fentanyl. A decline in DMP identifications began in 2024 Q1, coinciding with the appearance of other cathinones, including DMP's structural isomer, N-isopropyl butylone (NiPB), and alpha-PiHPP (iso-PV8), among others. However, as of 2025 Q1, no single SC has emerged as a new dominant substance prompting the toxicology community to continuously monitor the evolving landscape of SCs particularly through seized drug and toxicology exhibits in Florida.