What is cychlorphine? Learn about the emerging synthetic opioid, its potency, overdose risk, alternate names and why officials are concerned.
The illicit drug supply continues to change, with new synthetic opioids appearing alongside fentanyl and other substances. One of the newest drugs raising concern is cychlorphine, a highly potent synthetic opioid that has been connected to fatal overdoses in the United States and abroad.
Cychlorphine is still relatively unfamiliar to the general public, but detections have increased quickly enough to draw warnings from forensic researchers, international health authorities, and the Drug Enforcement Administration (DEA). In August 2026, the DEA placed cychlorphine into Schedule I of the Controlled Substances Act, citing an imminent hazard to public safety.
Here is what people should know about cychlorphine, including why it is dangerous and what to do if an opioid overdose is suspected.
What Is Cychlorphine?
Cychlorphine is a synthetic opioid belonging to a group of drugs known as orphine analogues, sometimes shortened to “orphines.” These drugs are chemically distinct from both fentanyl and nitazenes, another class of powerful synthetic opioids that has received increasing attention in recent years.
Like fentanyl and other opioids, cychlorphine activates opioid receptors in the brain. This can produce effects such as pain relief, sedation and euphoria, but it can also dangerously suppress breathing. Severe respiratory depression is one of the primary reasons opioid overdoses can become fatal.
There is no approved medical use for cychlorphine in the United States.
Cychlorphine Street Names and Other Names
Because cychlorphine is relatively new to the illicit drug supply, there does not currently appear to be a widely established street name or nickname for the drug. Major international and U.S. sources primarily identify it by its chemical and scientific names.
You may also see the term “cylorphine” online. This is a spelling variation or misspelling of cychlorphine, rather than the name of a separate substance.
As the drug becomes more prevalent, additional street names will likely develop. For now, it is important not to assume that cychlorphine will necessarily be sold under its own name at all.
Why Is Cychlorphine Dangerous?
One of the biggest concerns is its potency. Early laboratory research indicates that cychlorphine has very strong activity at opioid receptors. Studies from CFSRE have reported in-vitro findings suggesting a potency 10 times greater than fentanyl, although research into the drug is still developing.
That does not mean every sample containing cychlorphine is automatically “10 times stronger than fentanyl.” Potency in laboratory testing and the effects of an illicit drug mixture are not the same thing. Concentration, other substances in the mixture, tolerance and individual health factors can all influence overdose risk.
What is clear is that cychlorphine is a very powerful opioid capable of causing profound sedation and respiratory depression.
Cychlorphine Is Showing Up in the U.S. Drug Supply
Cychlorphine began appearing in forensic testing in North America in 2024, with detections increasing substantially during 2025 and 2026. CFSRE issued a public alert in January 2026 after identifying a rise in fatal overdose cases involving the drug.
DEA data have since documented N-propionitrile chlorphine in 19 states, including Massachusetts. The agency has also identified cychlorphine in samples containing fentanyl, xylazine, medetomidine and other substances.
That is an important part of the risk. Someone does not necessarily need to seek out cychlorphine intentionally to be exposed to it. Novel synthetic opioids can appear within a drug supply containing multiple substances, and the person using the drug may have no idea what is actually present.
Can Fentanyl Test Strips Detect Cychlorphine?
Standard fentanyl test strips do not detect cychlorphine itself. UNODC has specifically warned that emerging orphine analogues are not detected by fentanyl or nitazene test strips.
This means a negative fentanyl test cannot establish that a drug is free of powerful synthetic opioids. As the illicit drug supply becomes more polluted, identifying every substance present using consumer test strips becomes increasingly difficult.
What Does a Cychlorphine Overdose Look Like?
Because cychlorphine acts as an opioid, an overdose can resemble an overdose involving fentanyl, heroin or other opioids. Warning signs can include:
- Being unconscious or unable to wake up
- Very slow, shallow or stopped breathing
- Choking, snoring or gurgling sounds from someone who cannot be awakened
- Small, constricted or “pinpoint” pupils
- Pale, blue, gray or otherwise discolored lips, skin or fingernails
If you are unsure whether someone is overdosing, the CDC recommends treating the situation as an overdose.
Does Naloxone Work on Cychlorphine?
Naloxone should be administered when a cychlorphine or other opioid overdose is suspected. Naloxone works by blocking opioid receptors and can restore breathing during an opioid overdose.
Give naloxone if it is available and call 911 immediately. If normal breathing does not return within two to three minutes, the CDC recommends administering another dose of naloxone. Stay with the person until emergency help arrives.
The exact substance involved does not need to be known before using naloxone. If opioid overdose is a possibility, acting quickly can save a life.
What People Should Know About Cychlorphine
Cychlorphine is another example of how rapidly the illicit drug supply can change. For people struggling with opioid use, that unpredictability adds another layer of risk. Even someone who believes they understand their tolerance or knows what to look for may encounter an unfamiliar substance or combination of substances.
If you or someone you care about is struggling with opioid use, help is available. Northstar Recovery Center provides outpatient substance use treatment throughout Massachusetts, with in-person and virtual options designed to help people begin and sustain recovery.
Call 888-339-5756 to learn more about our programs and services.
