Fentanyl now leading cause of US overdose deaths

The US is in the midst of an epidemic of drug overdose deaths, with nearly 65,000 people killed in 2016, a 21% jump from a year earlier. Leading the increase is the surge in deaths due to fentanyls. Synthetic opioids doubled their share of the previous year's toll. The increase alarms because fentanyl only arrived in the illicit drug supply around 2012.