About five people in the US are dying every hour from opioids. From Dr. Frank Huyler at nydailynews.com:

OxyContin wasn’t a new drug. It was simply a new pill designed to release an old drug — oxycodone — more slowly. Oxycodone was first synthesized in 1916, and is closely related to heroin. (TOBY TALBOT/AP)
In countries like the United States, any decline in life expectancy is unheard of. It speaks to very large forces at work, like World War II, or HIV.
In this case, opioid overdoses are to blame. They have quadrupled since 1999, and are continuing to rise. Right now that epidemic is killing more people in the U.S. than AIDS at its peak. About five people are dying per hour — all day, every day.
The story of the opioid epidemic has been told before by the media. But it hasn’t been examined nearly enough. It’s a story that should prompt far larger questions about our country, its values, and its institutions than we have asked.
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Opioids affect us in complex and mysterious ways . They don’t stop sensation, like local anesthetics. Instead, these drugs work by activating natural opioid receptors in our brains. They change our experience of pain. They replace pain, in part, with pleasure.
Pain thresholds are built into us for powerful evolutionary reasons. Opioids make us feel good in the short term, but they also distort essential mechanisms necessary for survival in a Darwinian world.
Tolerance is the body’s natural attempt to restore those mechanisms. We become less sensitive to opioids, and need higher doses for the same effect. Tolerance is the first step toward physical addiction; the two are linked. As tolerance rises, the risk of overdose and death follows closely behind.