Cyclorphine synthetic drug linked to fatal overdoses in the US

Health officials are warning of a potent and deadly new synthetic designer drug called cyclorphine, which has emerged in the United States. The drug is described as being up to ten times more powerful than fentanyl and is frequently mixed with other substances such as methamphetamine, cocaine, and bromazolam without the user's knowledge.

The Office of National Drug Control Policy (ONDCP) issued a threat advisory regarding the substance, noting its connection to dozens of deaths across the country. A significant portion of confirmed overdoses occurred in Tennessee, where the Knox County Regional Forensic Center has tracked at least 41 deaths linked to the drug between July 2025 and February 2026.

In response to the rising danger, the Drug Enforcement Administration (DEA) issued a temporary order categorizing cyclorphine as a Schedule I substance, placing it in the same legal category as heroin and LSD. Law enforcement in San Francisco recently conducted raids resulting in the arrest of four suspects and the seizure of over 20,000 counterfeit pills.