Fentanyl, the powerful drug that killed Prince, presents growing threat

By Fiona Ortiz CHICAGO (Reuters) - Fentanyl, a powerful painkiller that a medical examiner identified as the drug that killed the superstar Prince six weeks ago, has been responsible for an epidemic of overdose deaths around the United States, according to federal officials. The most potent narcotic known, it is a man-made opioid 50 times stronger than heroin and 100 times more so than morphine, according to the U.S. Centers for Disease Control website. The agency says illegally manufactured non-pharmaceutical fentanyl, and related overdoses, are a rising problem.