Public health officials are issuing a warning after recording Los Angeles County's first death linked to a new synthetic opioid that has made its way into Southern California's illicit drug supply.
N-propionitrile chlorphine, also known simply as cychlorphine, is "more potent than fentanyl" and cannot be detected with traditional fentanyl test strips, according to the L.A. County Department of Public Health.
"The County of Los Angeles Medical Examiner recently identified the drug as a cause of death that occurred in February 2026," the agency said in a written statement. "This fatality due to cychlorphine is the first confirmation of cychlorphine’s presence in the local illicit drug supply."
The drug, along with nitazenes, is among a series of
recently introduced synthetic opioids drawing attention and concern from officials at the local, state, and federal levels.
Chlorphine was classified by the DEA as a Schedule I drug in August, which banned possession or sale of the substance.
What is cychlorphine?
Cychlorphine is an opioid "that is more potent than fentanyl and can cause respiratory depression and death," according to the LACDPH statement. "
"Cychlorphine is particularly dangerous due to its strength, where a very small amount can cause someone to stop breathing," the statement continued. "It is also currently undetectable by fentanyl testing strips and is being mixed into the illicit drug supply without people knowing."
The danger is increased when cychorphine is mixed with alcohol or other drugs, experts warned.
Officials first discovered the drug in the U.S. in 2024, county officials said. It has since turned up in 19 states.
It can be found as a powder, manufactured into counterfeit prescription pills, crystals, and liquids.
The Golden State saw its first death linked to cychlorphine in Northern California in April, public health officials said.
"While cychlorphine has been more prevalent in the illicit drug supply in other parts of the U.S., Public Health is monitoring for changes in the prevalence of cychlorphine in Los Angeles County’s illicit drug supply," the statement added.
As authorities crack down on existing nitazene drugs through regulation, law enforcement efforts and scheduling restrictions, new versions of the powerful synthetic opioids often emerge, according to the DEA. The agency says it has identified 22 nitazene compounds since 2020, and 21 are classified as Schedule I controlled substances.
Does naloxone work in cychlorphine overdoses?
The safest way to avoid the danger posed by cychlorphine and other synthetic opioids is to abstain from illicit drugs, which could be laced or contaminated with the powerful drug
But the risk of sudden death can be reduced through the use of naloxone, an anti-overdose medication also known as Narcan.
"Naloxone can reverse an opioid overdose and successfully restore breathing to reverse the effects of opioids, including cychlorphine," the LACDPH statement said. "Naloxone can be administered through the nose or as an intramuscular injection to save their life. Both methods are equally effective."
Additional measures suggested to limit risk to those who do use drugs included never using alone, starting with small doses, and avoiding mixing substances.
"In an emergency, call 911 and administer naloxone," the statement said. "Multiple doses may be necessary."
This article originally appeared on Palm Springs Desert Sun: L.A. County sees first death from new synthetic opioid cychlorphine
