Isotonitazene emerges as potent synthetic opioid threat

The synthetic opioid isotonitazene, commonly referred to as ‘ISO’, is emerging as a significant threat in illegal drug markets. According to the United Nations Office on Drugs and Crime (UNODC) 2026 World Drug Report, ISO belongs to the nitazene family, a group of synthetic substances that can be significantly more potent than fentanyl.

Reports indicate that ISO can be between five and nine times more potent than fentanyl. Specifically, the most common nitazene (ISO) is estimated to be between 250 and 900 times more potent than morphine, while the most potent variants may reach up to 4,300 times the potency of morphine. These substances are synthetically designed to mimic traditional opiates and are highly addictive.

The appearance of nitazenes and orfinas has caused acute medical emergencies and fatalities across a diverse range of countries. In North America, concerns have been raised regarding the production of these drugs, with allegations involving Mexican criminal organizations operating synthesis laboratories in regions including Canada.