January 23, 2023
New Potent Synthetic Opioid—N-Desethyl Isotonitazene—Proliferating Among Recreational Drug Supply in USA

N-Desethyl isotonitazene is a new synthetic opioid bearing structural resemblance to isotonitazene and recently emergent nitazene analogues. N-Desethyl isotonitazene is dissimilar in chemical structure to fentanyl, the synthetic opioid most commonly encountered, but this subclass of new opioids has been proliferating in the wake of the scheduling of fentanyl analogues. N-Desethyl isotonitazene is a known metabolite of isotonitazene; however, it has now emerged as a primary drug in its own right. Most nitazene analogues encountered retain opioid receptor activity and potency similar to or greater than fentanyl. In vitro pharmacological data show that N-desethyl isotonitazene is an active opioid agonist and is approximately 20x more potent than fentanyl. In December 2022, N-desethyl isotonitazene was first reported by NPS Discovery (Florida); however, first identifications were observed as early as September 2022. To date, seven drug material samples (“dope” powders) collected from the Philadelphia drug supply have tested positive for N-desethyl isotonitazene. In December 2022, the Philadelphia Department of Public Health issued an alert regarding the discovery of this new nitazene analogue in the city’s drug supply. The toxicity of N-desethyl isotonitazene has not been examined or reported but recent association with overdoses among people who use drugs leads professionals to believe this synthetic opioid has the potential to cause harm and is of high public health concern.