A medical examiner announced on Thursday that music legend Prince died of a self-administered dose of the synthetic opioid fentanyl, unleashing a torrent of headlines about the dangerously powerful narcotic that is “sweeping the U.S.”

Fentanyl isn’t a new drug. It began its long run as a first-line surgical analgesic in 1968, and since the introduction of the transdermal patch in the 1990s, has become one of the most commonly prescribed narcotics for treating moderate-to-severe cancer pain.

However, its profile as a street drug has grown precipitously over the past several years, as America has found itself in the grips of a crippling epidemic of opioid abuse.