Nitazenes
Definition
A class of benzimidazole-based synthetic opioids structurally unrelated to fentanyl but with potent mu-opioid receptor agonism. Isotonitazene, metonitazene, and protonitazene have been responsible for overdose deaths in the US, UK, and EU since 2019.
- Chemical class
- Benzimidazole-based synthetic opioids
- Mechanism
- Potent mu-opioid receptor agonism
- Examples
- Isotonitazene, metonitazene, protonitazene
- Emergence
- Overdose deaths in US, UK, EU since 2019
Common questions
Why can a fentanyl screen miss a nitazene in a toxicology case?+
Nitazenes are structurally unrelated to fentanyl, so fentanyl-specific immunoassays and some targeted panels can miss them. Confirmation requires LC-MS/MS methods that include nitazene-specific transitions or a broader untargeted screen.
Why have nitazenes become more common in the illicit opioid supply?+
They emerged as fentanyl analogues came under tighter drug scheduling, and their high receptor potency means a small quantity mixed into a counterfeit pill or heroin batch can deliver a fatal dose.
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