Officials warn cychlorphine is spreading across states

Health officials in multiple states have warned about rising reports of cychlorphine in the illicit drug supply. The White House Office of National Drug Control Policy (ONDCP) said the synthetic opioid is up to 10 times more potent than fentanyl and cannot be detected by drug test strips or opioid urine screens.

ONDCP reported 106 cases in 10 states in 2025, up from one report in 2024. Tennessee accounted for 41 of the 55 cychlorphine-involved overdose deaths reported nationwide from July 2025 to February 2026. A July study in the Journal of Pain Research reported that at least 24 states had overdoses or deaths related to cychlorphine as of March. ONDCP said the drug can be mixed with fentanyl or other drugs, or found on its own. Healio quoted clinicians who said suspected overdoses should be treated based on symptoms, since tests may not identify cychlorphine. Naloxone remains effective, but patients may need higher or repeated doses, according to an expert quoted by Healio.