Dangerous New Opioids Raise Overdose Risk

San Francisco health officials issued a public warning on April 24 after an overdose death earlier this month became the city’s first linked to cychlorphine. (kron4.com) (sfexaminer.com) Cychlorphine is a lab-made opioid, like fentanyl but stronger, and San Francisco officials said it is estimated to be about 10 times more potent than fentanyl. (kron4.com) (dea.gov) The victim is believed to have taken counterfeit pills. Toxicology found cychlorphine, N-desethyl isotonitazene, and ethyl bromazolam, and the Department of Public Health said fentanyl was not detected. (kron4.com) (sfexaminer.com) That combination changes the usual overdose playbook. Fentanyl test strips do not detect cychlorphine, so a tool many users rely on can miss the drug entirely. (kron4.com) (nwvcil.org) Nitazenes are another class of synthetic opioids showing up in the U.S. drug supply. The Drug Enforcement Administration said some nitazenes can match or exceed fentanyl’s potency and can sharply raise the risk of fatal respiratory arrest at very small doses. (dea.gov) (publichealth.lacounty.gov) San Francisco’s warning also comes after the Drug Enforcement Administration’s local office separately warned in late 2025 that it had seized 5,000 counterfeit pills containing carfentanil in the Bay Area. The agency said carfentanil is about 100 times more lethal than fentanyl. (nbcbayarea.com) The city’s overdose crisis had eased in 2025, when annual deaths fell to their lowest level in several years, according to the San Francisco Examiner. But the Office of the Chief Medical Examiner still reported 148 accidental overdose deaths in the first three months of 2026. (sfexaminer.com) (sfgov.org) Health officials told residents to carry naloxone and use it in any suspected opioid overdose. Los Angeles County public health officials have also warned that overdoses involving nitazenes can be reversed with naloxone but may require multiple doses. (sfexaminer.com) (publichealth.lacounty.gov) The immediate problem in San Francisco is not just one new drug name. It is that counterfeit pills now appear to contain opioids stronger than fentanyl that standard strip testing can miss. (kron4.com) (dea.gov)