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New Synthetic Opioid Protonitazene Increasing in Prevalence as “Nitazenes” Gain Traction Across the United States and Canada

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Date Published

This public 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, protonitazene.


This brief document provides information about the emergent synthetic opioid, protonitazene, which was first identified in the U.S. toxicology samples in the May 2021. The document provides a general background about synthetic opioids, noting that this new opioid exhibits potency similar to other recently emergent “nitazene” opioids and approximately three times more potent than fentanyl. The announcement also provides demographic information about users, including age and sex, and geographical distribution in the U.S. The fact sheet also depicts the structure of the protonitazene molecule; provides recommendations for public health, clinicians, medical examiners and coroners, and laboratories; and informs that NPS rapid testing is now available.

Date Published: January 1, 2021