U.S. flag

An official website of the United States government, Department of Justice.

Etodesnitazene — New Synthetic Opioid Identified During Forensic Death Investigations in the United States and Canada

NCJ Number
Date Published

This alert describes a new synthetic opioid, edtodesnitazene, identified in forensic death investigations in the United States and Canada over the past two years.


Etodesnitazene is a new synthetic opioid bearing structural resemblance to etonitazene, a synthetic opioid that is nationally and internationally controlled. The toxicity of etodesnitazene has not been examined or reported but recent association with death among people who use drugs leads professionals to believe this synthetic opioid retains the potential to cause harm and is of public health concern. Etodesnitazene is dissimilar in structure to synthetic opioids typically encountered in forensic casework (e.g., fentanyl, heroin); however, several analogues of this series (known as “nitazenes”) have recently emerged in several countries. In vitro pharmacological data show that etodesnitazene is an active opioid agonist that is approximately four times less potent than fentanyl (a common phenomenon for analogues missing the 5-nitro group) but approximately six times more potent than morphine. Etodesnitazene was first reported by NPS Discovery in February 2021 following initial detection in a toxicology case. To date, ten blood and/or urine specimens associated with postmortem death investigations or clinical intoxications in the United States and Canada were confirmed to contain etodesnitazene. Identifications of etodesnitazene have also been reported from organizations in Europe.

Date Published: January 1, 2021