Isotocyanozene (5-cyano-isotodesnitazene) is a benzimidazole opioid analogue of isotonitazene which has been sold as a designer drug. It was first prospectively observed in a toxicological sample in Scotland, United Kingdom in 2025, and was presumed to have opioid effects. It has been identified by the drug checking service CanTEST, Australia in September 2025 as an expected 'opioid' sample, and then later as an expected 'benzodiazepine' sample. Its in vitro biological activity is close to that of fentanyl.