New synthetic opioid cychlorphine linked to dozens of U.S. deaths

A synthetic opioid named cychlorphine, which is up to 10 times stronger than fentanyl, has been linked to dozens of overdose deaths in the United States since late 2025, according to reports from wsyr.iheart.com and other iHeart outlets.

The White House Office of National Drug Control Policy (ONDCP) issued a drug threat notice in April 2026 stating cychlorphine has appeared in every region of the country, with significant clusters of cases in Tennessee, Ohio, and Texas. Between July 2025 and February 2026, at least 55 deaths nationwide were attributed to the drug, with Tennessee alone reporting 41 fatalities.

Cychlorphine is classified as a novel synthetic opioid known as an orphine and is distinct from fentanyl. Like other opioids, it can slow or stop breathing, which can be fatal especially in high doses. The drug has been found both alone and mixed with other substances such as fentanyl, methamphetamine, cocaine, and sedatives.

One challenge with cychlorphine is that it cannot be detected by routine hospital urine screens or common fentanyl test strips, creating a diagnostic blind spot that complicates timely overdose response, according to an anesthesiology expert cited by Helio.

Health officials recommend administering naloxone (Narcan) immediately if an opioid overdose is suspected and calling 911. While naloxone remains effective against cychlorphine, its potency often requires multiple doses and extended medical monitoring to prevent fatal outcomes.

The drug has also been found in counterfeit pills resembling prescription medications, raising concerns about accidental exposure, particularly among teens and young adults.