Exploring the pharmaco-toxicology of nitazenes: insights and applications from bench to field

2-benzylbenzimidazole core – commonly referred to as ‘nitazenes’ - have increased in prevalence. By the end of 2025, 25 distinct
nitazene analogues had been reported to the European Union Drugs Agency (EUDA), with evidence of increasing availability at the street level. Pharmacological studies have demonstrated that many nitazene analogues, as well as several metabolites, display high activity at the µ-opioid receptor, with several exceeding fentanyl in potency. This high potency, combined with their unpredictability on the recreational drug market, has been associated with a growing number of intoxications and fatalities worldwide.
In response to these challenges, recent research has explored a range of complementary approaches, including the application of an in vitro bioassay for the functional characterization and universal detection of nitazenes and other NSOs.
Further complementing analytical data, activity-based methods enable the determination of opioid activity equivalents, thereby supporting the interpretation of forensic cases involving novel opioids. In this context, this presentation will review the current state of knowledge on the pharmaco-toxicology of nitazene opioids, approaches for their detection in authentic drug material – ranging from fielddeployable test strips to laboratory-based activity profiling - and emerging trends, with an outlook on future directions.