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N-Pyrrolidino Etonitazene (NPS Opioid)

NCJ Number
Date Published
13 pages

This purpose for this toolkit is to notify public health and safety, law enforcement, first responders, clinicians, medical examiners and coroners, forensic and clinical laboratory personnel, and all other related communities about new information regarding the emergent synthetic opioid, N-pyrrolidino etonitazene.


The NPS Discovery Toolkit is a consolidation of The Center for Forensic Science Research and Education (CFSRE) program outcomes into a comprehensive document that provides relevant information about the characterization of a specified novel psychoactive substance (NPS): N-pyrrolidino etonitazene. This toolkit includes basic drug information, date of first appearance, prevalence, quarterly trend reports, geographical trends, demographics, poly-drug combinations (including with other NPS), metabolism, methods for identification and confirmation, reference concentration ranges, and more. This toolkit is designed to serve as a one-stop resource for scientists and interested individuals looking for all-inclusive information about the new drug, N-pyrrolidino etonitazene. The summary of the drug describes its origins and drug analogues, as well as recent in vitro pharmacological data conclusions. The document also provides demographics information from overdose cases; geographic distribution; and recommendations for public health, clinicians, medical examiners (MEs) and coroners, and laboratories. The toolkit also provides current data on the status of NPS opioid prevalence and positivity within the U.S.; drug monograph which includes the chemical formula, molecular weight, exact mass; and analytical methods for the analysis of N-pyrrolidino etonitazene, including two instrumental approaches which provide a starting point for laboratories, as well as mass spectrometer setpoints which can be used to initiate ion monitoring or novel surveillance.

Date Published: January 1, 2022