Federal Public-Health Alert: Fentanyl Is Now Commonly Cut with Xylazine, Medetomidine, Cychlorphine, and Nitazenes

What the advisory said

On May 13, the DEA and state public-health officials in at least seven states (AZ, CA, GA, IL, NC, TX, FL among them) issued coordinated warnings that fentanyl is now commonly being cut with substances not approved for human use: the veterinary sedatives xylazine and medetomidine, the synthetic opioid cychlorphine (approximately 10x fentanyl potency), and nitazene-class analogues. The advisory follows the DEA’s May 12 cychlorphine release we covered yesterday and a separate CDC HAN on medetomidine earlier in the year.

The trend data is striking. Per NPR’s April analysis, medetomidine reports submitted to the National Forensic Laboratory Information System rose 950% from 2023 to 2024 (247 → 2,616) and another 215% from 2024 to 2025 (→ 8,233). Medetomidine prevalence in opioid samples rose from 4% in May 2024 to 37% in October 2025. This is one of the fastest supply-side shifts the U.S. illicit market has produced in a decade.

What people in or around recovery should know

Two facts matter most for harm reduction. First, naloxone does not reverse xylazine or medetomidine — they are not opioids. If someone overdoses on a fentanyl supply containing these sedatives, naloxone may revive breathing partially or not at all, and additional doses do not fix the sedation. Calling 911 still matters: emergency airway management and ventilation are what work. Second, multiple naloxone doses may be needed for the fentanyl + cychlorphine combination because of cychlorphine’s higher potency. The takeaway is the same that harm-reduction groups have been repeating for two years: carry naloxone, carry more than you think you need, and never use alone.

The supply-side picture is now unambiguously worse than it was 18 months ago. The Arizona +17.31% YoY overdose increase we covered in yesterday’s featured and the SAMHSA test-strip funding cuts are not coincidences — they are the same story.