[4][5][6][7][8] While several substances in this class have found applications in research, they have never been used in clinical medicine due to their profound risk of respiratory depression and death.
[10][11][12] Isotonitazene was first identified in samples of illicit drugs, and implicated in opioid overdose deaths in Europe, Canada, and the United States beginning in 2019.
[16][17][18][19][20][21][22][23][24][25][26][excessive citations] A 2019 publication[27] has shown the possibility the previously assumed binding position of the benzimidazole class,[28] acting as a semi-rigid fentanyl analogue may be incorrect.
In this analysis, it is noted, etonitazene now more closely matches another, separate mu-specific region, sharing only a small area in common with the fentanyl class.
While compounds from this class are sometimes incorrectly referred to as "nitazene",[30] the 4 unsubstituted compound nitazene itself is of relatively low potency and has not been reported as a designer drug, with most cases of abuse and overdose linked to more potent derivatives such as metonitazene, protonitazene, isotonitazene, etonitazepyne and etodesnitazene.