Global spread of isotonitazene synthetic opioids

The synthetic opioid isotonitazene, or ‘ISO’, has emerged as a significant threat within illegal drug markets. Part of the nitazene family, ISO is reported to be significantly more potent than fentanyl, with some variants estimated to be up to 4,300 times more potent than morphine. Early reports highlighted concerns regarding production by criminal organizations in North America, specifically involving laboratories in Mexico and Canada.

As the situation developed, the United Nations Office on Drugs and Crime (UNODC) warned of a rapid global expansion. The 2026 World Drug Report indicated that 34 varieties of nitazenes are circulating in at least 37 countries, including significant presence in Europe, North America, and Oceania. Specific instances of impact include Estonia, where 35% of analyzed syringes were contaminated, and the United States, where ISO has been linked to over one thousand deaths across 13 states.

The UNODC noted that ISO poses a unique public health risk because traditional rapid testing methods and reagent strips often fail to detect it, increasing the danger of fatal respiratory arrest. The transition from plant-based opiates to these synthetic alternatives may signal a permanent shift in the global opioid market.