Cychlorphine, a synthetic opioid reportedly up to 10 times more potent than fentanyl, has been linked to at least 55 deaths across the U.S.
https://www.foxnews.com/health/super-drug-10-times-stronger-fentanyl-linked-deaths-multiple-states
https://www.foxnews.com/health/super-drug-10-times-stronger-fentanyl-linked-deaths-multiple-states