Isotonitazene, a synthetic opioid from an emerging family: The nitazenes.

From 2019, in the United States and Europe, the synthetic opioid market has diversified with the appearance of the 2-benzylbenzimidazole family, commonly named "nitazenes". In vitro studies show that these synthetic opioids have much higher affinities on μ-opioid receptors: 100 times more than morphine, and slightly higher than fentanyl for isotonitazene, increasing the risk of overdose. In south of France, isotonitazene (IZN) was identified for the first time in March 2023.