Cychlorphine Is in the Supply and Your Test Strips Won't Catch It

When the White House Office of National Drug Control Policy issues a Drug Threat Notice, pay attention. ONDCP has never issued one before. The first one is about cychlorphine, a synthetic opioid that originated in Chinese labs in 2024, appeared in European drug supplies in summer 2025, and has now been confirmed in 10 U.S. states spanning all four census regions.

Here’s the part that matters most for harm reduction practice: cychlorphine is not expected to appear on standard fentanyl test strips or routine opioid urine screens. Someone who tests their supply for fentanyl and gets a clean strip is not testing for cychlorphine. The two facts together — higher potency, invisible to current detection — are why ONDCP escalated to a formal threat notice rather than a DEA advisory.

The drug is estimated to be up to 10 times more potent than fentanyl, meaning a lethal dose is proportionally smaller. The DEA issued its own public safety advisory on May 12, warning that overdoses may require multiple doses of naloxone to reverse — the same multi-dose challenge that drove the push for higher-concentration naloxone formulations in communities with heavy xylazine contamination. Cychlorphine has been found mixed with fentanyl, methamphetamine, cocaine, and bromazolam, and it has also appeared independently in seized counterfeit oxycodone tablets marked “M30” or “K56.” Fifty-five deaths have been linked to it between 2025 and now, with the highest concentrations reported in Ohio, Texas, and Tennessee.

Filter Magazine’s June 3 analysis by Kastalia Medrano argues that cychlorphine itself is not the real problem — that the structural issue is a drug supply that incentivizes ever-more-potent synthetic analogues as enforcement pushes against each prior compound. That argument is analytically correct and also not actionable today. Today, people are using test strips that were designed for fentanyl, in a supply chain that now includes something fentanyl test strips can’t see.

For harm reduction organizations, the immediate implication is narrow and urgent: the test strip infrastructure that was built over the past several years is now one step behind the supply. Programs operating on tight budgets that have just normalized fentanyl test strip distribution need to know that “negative fentanyl test” no longer means “no potent synthetic opioid present.” The expected development is that cychlorphine-specific testing technology will follow — it always does — but there is a window right now where the detection gap is live.

Carry naloxone. Carry more of it. Never use alone.

Rize Recovery tracks naloxone distribution points and harm reduction services across Arizona. See the harm reduction directory at rizerecovery.com/find-help.