Using heroin can kill you, but it may not be in the way you think.
Drug overdose deaths in the United States have risen steadily since 1970. Painkillers actually kill more Americans than heroin and cocaine combined, according to the Centers for Disease Control, but heroin is still among the main killers of illegal drug users. One in 10 heroin overdoses ends in death.
In 2011, 4.2 million Americans over the age of 11 had tried heroin at least once, according to the National Institute on Drug Abuse. An estimated 23% of them will become addicts. And it's addicts who die more frequently than new users, studies show.
Heroin in the body turns into morphine. Morphine has a chemical structure similar to endorphins -- the chemicals your brain makes when you feel stressed out or are in pain. Endorphins inhibit your neurons from firing, so they halt pain and create a good feeling.
Morphine, acting like your endorphins, binds to molecules in your brain called opioid receptors. When those receptors are blocked, that creates a high. Most people die from heroin overdoses when their bodies forget to breathe.
"Heroin makes someone calm and a little bit sleepy, but if you take too much then you can fall asleep, and when you are asleep your respiratory drive shuts down," said Dr. Karen Drexler, director of the addiction psychiatry residency training program and an associate professor in Emory University's psychiatry and behavioral sciences department.
"Usually when you are sleeping, your body naturally remembers to breathe. In the case of a heroin overdose, you fall asleep and essentially your body forgets."
A heroin overdose can also cause your blood pressure to dip significantly and cause your heart to fail.
Studies show intravenous heroin users are 300 times more likely to die from infectious endocarditis, an infection of the surface of the heart.
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