What is fentanyl, the drug that reportedly killed Prince?

The shocking results were revealed in a newly surfaced toxicology report.

In the aftermath of Prince’s sudden death on April 21, 2016, questions swirled as to what caused the iconic performer to collapse in an elevator inside his Minnesota home.

Data released after his death showed he died of an overdose, but the amount was unclear. This week, thanks to a toxicology report obtained by the Associated Press, America got its answer. The answer involves a drug this opioid-gripped nation is, sadly, well acquainted with: fentanyl. As the strongest man-made opioid on earth, fentanyl is responsible for thousands of deaths in the U.S. each year. Either sold alone or laced into heroin, fentanyl is an exceptionally potent painkiller that should only be used under a doctor’s supervision — but too often it isn’t.

While it’s not possible to say exactly how much fentanyl is lethal (each individual tolerates opioids differently), there are minimums that have proved deadly in certain individuals. Judging from Prince’s toxicology report, the singer far surpassed them. The fentanyl concentration in his blood was 67.8 micrograms per liter — 10 micrograms higher than what’s proven fatal in others. He also had 450 micrograms per kilogram in his liver, about six times higher than what seems to represent an overdose or a fatal amount.

Dr. Lewis Nelson, chairman of emergency medicine at Rutgers New Jersey Medical School, told the AP that the numbers represent “a pretty clear smoking gun.” Nelson added, “The amount in his blood is exceedingly high, even for somebody who is a chronic pain patient on fentanyl patches.”

(Photo: Getty Images)

The news is more than just illuminating as to what caused Prince’s death. It’s also telling about the power and availability of the drug itself. Fentanyl, for those unfamiliar, is a synthetic opioid similar to morphine, but 50 to 100 times stronger. Synthesized by a Belgian scientist in 1960, it was initially used as an intravenous pain medicine for surgeries. It was approved by the U.S. government for use in 1968.

With its unmatched ability to diminish pain, it wasn’t long before pharmaceutical companies were jumping on board, selling it as a patch, a pill, a lollipop, and a sublingual spray. Now marketed under brand names like Actiq and Fentora, it’s classified as a Schedule II substance by the Drug Enforcement Administration, meaning that — when used safely — it’s a safe option for pain management.

But because of its strength, and the feelings of euphoria that a painkiller of that caliber produces, fentanyl has a high potential for abuse. It’s something the black market has capitalized on in recent years, lacing it into heroin or selling it as counterfeit opioids in pill form. This underground market has proven extremely dangerous and thrust fentanyl into the spotlight as a lethal substance. Prince isn’t the exception when it comes to fentanyl — he’s the rule.

(Photo: Getty Images)

In March of 2015, the DEA issued a nationwide alert about the rise of fentanyl on the black market, specifically highlighting that the illicit versions had been sourced from places like China, where the market is unregulated. “Drug incidents and overdoses related to fentanyl are occurring at an alarming rate throughout the United States,” DEA administrator Michele M. Leonhart said at the time. “[They] represent a significant threat to public health and safety.”

The warnings did little to turn the tide on the growing fentanyl problem in America, one that persists today. Although it’s difficult to determine how many people have been killed by illicit fentanyl (the Centers for Disease Control and Prevention says it cannot distinguish between illicit and prescribed fentanyl), experts estimate that thousands die each year from its availability in the U.S.

The National Institute on Drug Abuse has attempted to track these numbers over time. Of the more than 64,000 overdose deaths they attributed to opioids in 2016, the biggest spike came from synthetic opioids like fentanyl — accounting for 20,000 of the deaths overall.

On top of being used without medical supervision, and laced into already-potent drugs like heroin, fentanyl proves incredibly difficult to counteract. It’s so strong, according to the National Institutes of Health, that it requires multiple rounds of naloxone — a drug used to counter an opioid overdose — in order to stop a fatal overdose. Whether that was an option in Prince’s case remains to be seen. The dose he had been administered — either by a doctor or himself — may have been too strong to respond to antioverdose medication of any kind.

But perhaps his death can be a lesson to those struggling with addiction themselves — or experiencing it in a loved one. Fentanyl, as the loss of Prince proves, is a formidable enemy.

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