Intoxications in an Australian Emergency Department Involving 'Nitazene' Benzylbenzimidazole Synthetic Opioids (Etodesnitazene, Butonitazene and Protonitazene).

Benzimidazole synthetic opioids are highly potent μ-opioid receptor agonists with heroin-like effects, including dose-dependent respiratory depression and a high risk of abuse and toxicity. Benzimidazoles were first detected in 2019 in Europe and Canada, with analytical confirmation of etodesnitazene, protonitazene and butonitazene in 2021. We report the first detections of these compounds in Australia, in two patients presenting with drug toxicity to Emergency Departments (EDs) in the state of Victoria.