Written by Megan Hilbert
Spoon Feed
Nitazenes (a class of synthetic opioids) entered the international drug market in 2019 and are becoming more frequently encountered substance in the ED.
A new(ish) drug has entered the streets…
This was a non-interventional observational cohort study that extracted data from the Prescription, Recreational, and Illicit Substance Evaluation (PRISE) Program database in New South Wales, Australia. They evaluated 27 cases of confirmed nitazene opioid exposures (20 overdose, 7 withdrawal), with the first case identified in April 2021.
Important information they found:
- The most common route of exposure was vaping (41%).
- Six separate nitazene formulations were identified (up to 40 exist).
- Only in 38% of cases were nitazene opiates specifically sought. In 52% of cases a non-opiate substance was sought (most commonly MDMA)––yikes!
- Naloxone was administered in 69% of the cases, but there was no unifying dose or pattern determined for repeat dosing identified (some required a drip).
- Patients presented with a broad clinical presentation from simple hypoventilation to cardiac arrest.
How will this change my practice?
When a patient comes in for an overdose or withdrawal, I always ask what drug they think they were using. If the toxidrome and symptoms they are presenting with don’t match with what would be expected, I take a moment to discuss adulterants and make them aware of what additional substances are out there (ie: xylazine and now, more frequently, nitazenes). My hope is that as providers we can improve public health education regarding these substances, with particular emphasis on patients who seek non-opiate substances. These patients in particular would likely benefit from being discharged with naloxone in addition to our patients who typically do “blues”.
Source
Clinical Experiences With the Nitazene Class of Synthetic Opioids: A Cohort Study. Ann Emerg Med. 2025 Nov;86(5):475-483. doi: 10.1016/j.annemergmed.2025.06.619. Epub 2025 Aug 14. PMID: 40810707.
