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Metonitazene (NPS Opioid)

NCJ Number
307385
Date Published
2021
Length
12 pages
Annotation

This announcement notifies public health and safety, law enforcement, first responders, clinicians, medical examiners and coroners, forensic and clinical laboratory personnel, and all other communities about new information surrounding the emergent synthetic opioid metonitazene.

Abstract

This announcement notifies public health and safety, law enforcement, first responders, clinicians, medical examiners and coroners, forensic and clinical laboratory personnel, and all other communities about new information surrounding the emergent synthetic opioid metonitazene. The toxicity of metonitazene has not been extensively studied, but recent association with drug user death leads professionals to believe this new synthetic opioid retains the potential to cause widespread harm and is of public health concern. Identifications of metonitazene have also been reported out of Europe. Metonitazene is a potent synthetic opioid bearing structural resemblance to etonitazene, a nationally and internationally controlled synthetic opioid. Metonitazene is dissimilar in structure to other synthetic opioids typically encountered in forensic casework. Synthetic opioids are chemically manufactured drugs, often accompanied with unknown potency and adverse effects or health risks. New synthetic opioids may be mixed with more traditional opioids, creating additional risk and danger for recreational drug users. Synthetic opioids may be distributed in powder or tablet form. In the United States, an alarming increase in the number of deaths linked to synthetic opioid use has been reported. The primary adverse effect associated with synthetic opioid use is respiratory depression, often leading to death. Metonitazene and similar analogues were first synthesized and reported in the literature in the 1950s. Pharmacological data suggest that this group of synthetic opioids have potency similar to or greater than fentanyl. Metonitazene was first reported by NPS Discovery after detection in a seized drug powder in July 2020. To date, metonitazene has been identified in eight blood specimens associated with postmortem death investigations in the United States. The appearance of metonitazene and its increasing occurrence appears to be linked to recent drug scheduling actions for isotonitazene (June 2020) and brorphine (December 2020), both past peak positivity based on examination of comprehensive toxicology data.

Date Published: January 1, 2021