Fentanyl
Fentanyl, a potent opioid agonist, was developed in the 1950s to fill a need for strong and rapid analgesia. Because of these characteristics, fentanyl is commonly used to treat chronic cancer pain or in anesthesia. Fentanyl is related to other opioids like [morphine] and [oxycodone].  Fentanyl's high potency has also made it a common adulterant in illicit drugs, especially heroin. In 2017, 47600 overdose deaths in the United States involved some opioid (over 2/3 of all overdose deaths). Opioid overdoses kill an average of 11 Canadians daily.  Fentanyl was FDA approved in 1968.