I keep hearing about fentanyl. What is it?

I keep hearing about fentanyl. What is it?

Deaths from fentanyl and other synthetic opioids (not including methadone), rose a staggering 72 percent in just one year, from 2014 to 2015. Government agencies and officials of all types are rightly concerned by what some are describing as the third wave of our ongoing opioid epidemic. Learn more.