Evidence map›Paper›PMID 42034717›Full record

ArticleArchives of toxicology2026

Fatal intoxications with nitazenes: postmortem findings, toxicology, and in vitro characterization at the μ-opioid receptor of six nitazene analogues.

Michael T Truver, Markus Roman, Munchelou M Gomonit, Henrik Gréen, Robert Kronstrand, Mattias Persson

Abstract read
PubMed Publisher
In one paragraph

Article in Archives of toxicology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Michael T TruverDepartment of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, 1200 SW 34th Drive, Gainesville, FL, 32607, USA. michael.truver@ufl.edu.ORCID 0000-0003-3747-5379
Markus RomanDepartment of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Artillerigatan 12, 587 58, Linköping, Sweden.
Munchelou M GomonitDepartment of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, 1200 SW 34th Drive, Gainesville, FL, 32607, USA.ORCID 0009-0009-8873-8993
Henrik GréenDepartment of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Artillerigatan 12, 587 58, Linköping, Sweden.ORCID 0000-0002-8015-5728
Robert KronstrandDepartment of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Artillerigatan 12, 587 58, Linköping, Sweden.ORCID 0000-0002-4222-9597
Mattias PerssonDepartment of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Artillerigatan 12, 587 58, Linköping, Sweden.ORCID 0000-0002-4383-2902

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Nitazenes constitute a structurally diverse class of non-fentanyl synthetic opioids that have rapidly emerged in the European illicit drug market since 2019. Bridging analytical, seized drug epidemiology, and interpretative gaps would support meaningful interpretation of nitazene-related deaths. This study presents a fit-for-purpose LC-MS/MS method for the quantitation of six nitazenes, etazene, isotonitazene, N-pyrrolidino isotonitazene, metonitazene, N-pyrrolidino metonitazene, and protonitazene in postmortem blood. The method was applied to analyze 57 nitazene-positive autopsy cases received between December 2020 and December 2024 by the Swedish National Board of Forensic Medicine. During this period, metonitazene (n = 38) and protonitazene (n = 10) were the most encountered nitazenes, with femoral blood concentrations in mono-intoxicated cases ranging from 0.3 to 34 ng/g and 1.7 to 4.9 ng/g respectively. Complementary in vitro MOR activation studies using AequoScreen® assays demonstrated that these nitazenes possess potencies (0.17-6.0 nM) and efficacies comparable to, or exceeding, those of fentanyl. The predominance of metonitazene prompted further investigation into its metabolism and stability profile, where analysis of authentic postmortem cases indicated the presence of three possible metabolites (N-desethyl, acetamido, 5-amino metonitazene) alongside other amino-containing degradation products. Further studies elucidating true metabolites from postmortem or storage-related breakdown products would support interpretation of nitazene exposure in casework. These findings provide an overview of nitazenes in Swedish forensic casework and address a critical gap in region-specific data, underscoring the need for sustained analytical vigilance and proactive toxicovigilance strategies to ensure timely detection and accurate interpretation of nitazene-related mortalities in an evolving drug landscape.

Indexed as

Analgesics, OpioidIllicit DrugsAdultAnimalsAutopsyBenzimidazolesChromatography, LiquidFemaleHumansMaleSwedenTandem Mass SpectrometryAnalgesics, OpioidBenzimidazolesIllicit DrugsnitazeneForensic toxicologyLC–MS/MSMetabolism and degradation of metonitazeneNitazenesNovel synthetic opioids (NSOs)μ-opioid receptor (MOR)

Identifiers

PMID42034717

What Socratic holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.