Metonitazene

{{Short description|Chemical compound (analgesic drug)}}

{{cs1 config|name-list-style=vanc}}

{{Drugbox

| drug_name =

| type =

| IUPAC_name = 2-[2-(4-Methoxybenzyl)-5-nitro-1H-benzimidazol-1-yl]-N,N-diethylethanamine

| image = metonitazene.svg

| width = 200

| alt =

| caption =

| tradename =

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| licence_US =

| pregnancy_AU =

| pregnancy_US =

| pregnancy_category =

| legal_BR = F1

| legal_DE = Anlage II

| legal_UK = Class A

| legal_US = Schedule I

| legal_status = Illegal in Sweden{{cite web|last1=Riksdagsförvaltningen|title=Förordning (1992:1554) om kontroll av narkotika Svensk författningssamling 1992:1992:1554 t.o.m. SFS 2021:301 - Riksdagen|url=https://www.riksdagen.se/sv/dokument-lagar/dokument/svensk-forfattningssamling/forordning-19921554-om-kontroll-av-narkotika_sfs-1992-1554|website=www.riksdagen.se|lang=sv}}

| routes_of_administration =

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| CAS_number_Ref = {{cascite|correct|CAS}}

| CAS_number = 14680-51-4

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = A7FF4K4CWB

| KEGG_Ref = {{keggcite|correct|kegg}}

| KEGG = C22727

| ATC_prefix =

| ATC_suffix =

| PubChem = 53316366

| DrugBank =

| ChemSpiderID = 81407756

| ChEBI = 234362

| C = 21

| H = 26

| N = 4

| O = 3

| melting_point =

| smiles = CCN(CC)CCN1C2=C(C=C(C=C2)[N+](=O)[O-])N=C1CC3=CC=C(C=C3)OC

| StdInChI = 1S/C21H26N4O3/c1-4-23(5-2)12-13-24-20-11-8-17(25(26)27)15-19(20)22-21(24)14-16-6-9-18(28-3)10-7-16/h6-11,15H,4-5,12-14H2,1-3H3

| StdInChIKey = HNGZTLMRQTVPBH-UHFFFAOYSA-N

}}

Metonitazene is an analgesic compound related to etonitazene,{{cite journal | vauthors = Vandeputte MM, Van Uytfanghe K, Layle NK, St Germaine DM, Iula DM, Stove CP | title = Synthesis, Chemical Characterization, and μ-Opioid Receptor Activity Assessment of the Emerging Group of "Nitazene" 2-Benzylbenzimidazole Synthetic Opioids | journal = ACS Chemical Neuroscience | volume = 12 | issue = 7 | pages = 1241–1251 | date = April 2021 | pmid = 33759494 | doi = 10.1021/acschemneuro.1c00064 | hdl-access = free | s2cid = 232337929 | hdl = 1854/LU-8714061 | url = https://biblio.ugent.be/publication/8714061 }}{{cite journal | vauthors = Ujváry I, Christie R, Evans-Brown M, Gallegos A, Jorge R, de Morais J, Sedefov R | title = DARK Classics in Chemical Neuroscience: Etonitazene and Related Benzimidazoles | journal = ACS Chemical Neuroscience | volume = 12 | issue = 7 | pages = 1072–1092 | date = April 2021 | pmid = 33760580 | doi = 10.1021/acschemneuro.1c00037 | s2cid = 232356192 }} which was first reported in 1957,{{cite journal | vauthors = Hunger A, Kebrle J, Rossi A, Hoffmann K | title = [Synthesis of analgesically active benzimidazole derivatives with basic substitutions] | journal = Experientia | volume = 13 | issue = 10 | pages = 400–401 | date = October 1957 | pmid = 13473817 | doi = 10.1007/bf02161116 | s2cid = 32179439 }} and has been shown to have approximately 100 times the potency of morphine by central routes of administration,{{cite web |title=Drug Trend Alert: Nitazenes |url=https://hamiltoncountyhealth.org/wp-content/uploads/2024/07/DrugTrendAlert_June2024.pdf |website=Hamilton County Public Health |publisher=Hamilton County, Ohio |access-date=16 June 2025}}{{cite journal| vauthors = Hunger VA, Kebrle J, Rossi A, Hoffmann K |date=1960|title=Benzimidazol-Derivate und verwandte Heterocyclen III. Synthese von 1-Aminoalkyl-2-nenzyl-nitro-benzimidazolen|journal=Helvetica Chimica Acta|language=en|volume=43|issue=4|pages=1032–1046|doi=10.1002/hlca.19600430412 }} but if used orally it has been shown to have approximately 10 times the potency of morphine.{{cite journal | vauthors = Bromig G | title = [New powerful analgetics and their clinical testing] | journal = Klinische Wochenschrift | volume = 36 | issue = 20 | pages = 960–963 | date = October 1958 | pmid = 13612082 | doi = 10.1007/bf01486702 | s2cid = 1023209 }}

Its effects are similar to other opioids such as fentanyl and heroin, including analgesia, euphoria, and sleepiness.{{cite journal | vauthors = Krotulski AJ, Papsun DM, Walton SE, Logan BK | title = Metonitazene in the United States-Forensic toxicology assessment of a potent new synthetic opioid using liquid chromatography mass spectrometry | journal = Drug Testing and Analysis | volume = 13 | issue = 10 | pages = 1697–1711 | date = October 2021 | pmid = 34137194 | doi = 10.1002/dta.3115 | s2cid = 235460764 }} Adverse effects include vomiting, and respiratory depression that can potentially be fatal.{{cite journal | vauthors = Montanari E, Madeo G, Pichini S, Busardò FP, Carlier J | title = Acute Intoxications and Fatalities Associated With Benzimidazole Opioid (Nitazene Analog) Use: A Systematic Review | journal = Therapeutic Drug Monitoring | volume = 44 | issue = 4 | pages = 494–510 | date = August 2022 | pmid = 35149665 | doi = 10.1097/FTD.0000000000000970 | s2cid = 246776288 }} Because of high dependency potential and dangerous adverse effects it has never been introduced into pharmacotherapy. It is instead commonly used in the illicit manufacture of counterfeit oxycodone opioid pills.{{cite web |title=A synthetic opioid stronger than fentanyl and hundreds of times more potent than heroin is emerging in Australia |url=https://www.abc.net.au/news/2024-06-25/nitazines-synthetic-opioid-warning-australia-overdose-deaths/104013774 |website=ABC News |access-date=25 June 2024 |language=en-AU |date=24 June 2024}}