A new and potent synthetic opioid called cychlorphine is quietly spreading through the US illicit drug supply — and it's flying under the radar of standard testing. Belonging to a class of drugs known as orphines (formally benzimidazol-2-ones), cychlorphine is estimated to be up to 10 times more potent than fentanyl and can cause life-threatening respiratory depression. First detected in the US in 2024, it has since surged dramatically, with a sharp spike beginning in late 2025.

A research letter published in JAMA Psychiatry analyzed data from 2020 through mid-2026 and found orphine-positive specimens in 22 states, with cychlorphine accounting for 72% of detections. The South and Midwest are hardest hit — Tennessee alone accounted for 35% of specimens. Polysubstance use is common, with fentanyl, benzodiazepines, and methamphetamine frequently detected alongside orphines. Experts believe China's 2025 scheduling of nitazene analogues may have opened the door for orphines to fill the market gap.

Key Takeaways:

• Standard drug test strips and hospital opioid urine screens cannot detect cychlorphine — specialized lab testing (e.g., LC-MS/MS) is required
• Naloxone remains effective but multiple doses may be needed given the drug's extreme potency
• At least 55 deaths have been linked to cychlorphine nationwide (2025–2026), with 41 in Tennessee alone
• Clinicians should treat suspected opioid overdose based on clinical presentation, not lab confirmation

Why it matters: Cychlorphine creates a dangerous diagnostic blind spot in emergency care. With no orphine-specific test strips available and deaths likely being undercounted, clinicians and public health officials need updated surveillance tools, clinical guidance, and expanded naloxone access.