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

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This announcement seeks to notify public health and public safety, law enforcement, clinicians, medical examiners and coroners, laboratory personnel, drug treatment providers, and other related communities about new information about the emergent synthetic opioid, N-desethyl isotonitazene.


This brief document provides information about the emergent synthetic opioid, N-desethyl isotonitazene, which has a structural resemblance to isotonitazene and the recently emergent nitazene analogues. N-Desethyl isotonitazene is dissimilar in chemical structure to fentanyl, although in vitro pharmacological data show that this molecule is approximately 20x more potent than fentanyl. This document provides a summary of N-desethyl isotonitazene, including facts about its emergence as well as structural analogues, toxicity, and adverse effects associated with the molecule. The announcement also notes geographical distribution in the U.S. along with a timeline of its discovery and spread; it depicts the structure of the N-desethyl isotonitazene molecule; and provides recommendations for public health, clinicians, medical examiners and coroners, and laboratories.

Date Published: January 1, 2023