Buy Etonitazene Powder - Research Chemicals - Global Chem Market. Etonitazene Powder is a synthetic opioid from the benzimidazole opioid family. It is relevant to forensic toxicology and emerging synthetic-opioid research because of its potent opioid activity and associated risks of serious toxicity. Compared with established pharmaceutical opioids, information concerning its human safety profile and clinical pharmacology is limited.