Emergence of Medetomidine in New York's Illicit Drug Supply.

AbstractNew York State and New York City health departments have closely monitored the emergence of medetomidine, a sedative that can cause prolonged sedation and a complex withdrawal syndrome, in the illicit drug supply. Drug checking and toxicology data first detected medetomidine in New York in mid-2024, and through 2025 it was identified in 25.1% of opioid samples analyzed. This Public Health Alerts report highlights state and local collaboration to detect emerging substances of concern in the illicit drug supply and to implement data-guided programmatic responses, including enhanced surveillance, public alerts, and medetomidine test strip distribution.