Why is heroin use soaring?
It's become a dirt-cheap alternative to the prescription opiates abused by millions of Americans. With a dose of heroin now selling for as little as $5 to $10, about 669,000 people admitted using heroin in 2012, almost double the number in 2007, according to the National Survey on Drug Use and Health. The crisis includes cities such as Chicago and New York, but heroin use has also spread to the suburbs and rural areas in the Midwest and New England. It now affects the middle class and the wealthy — underscored this month by the overdose death of actor Philip Seymour Hoffman, who was found with a needle in his arm and 50 glassine bags of the drug. Heroin addiction has grown so widespread in rural Vermont that Gov. Peter Shumlin devoted his entire State of the State address to the epidemic, which he said had become "a full-blown crisis" in his state. "It's everywhere," said DEA Special Agent James Hunt. "It is being used by the young, middle-aged, even cops' kids and soccer moms."

What is heroin's effect on users?
It delivers an instant euphoric high, temporarily releasing its users from all feelings of pain, depression, and anxiety. This rapturous sensation quickly creates a powerful physical and psychological craving for the drug. Processed from opium poppies, heroin is often injected, but can also be snorted, smoked, or eaten. About 23 percent of those who use heroin will become addicted, according to the National Institute on Drug Abuse. "By the time that you figure out it does destroy your life," said former addict Aram Homampour, "you've lost the power of choice."

Where is the heroin coming from?
A record opium crop in Afghanistan last year flooded the global market, but the majority of heroin consumed in the U.S. comes from Mexico — now the world's second-largest opium poppy cultivator. Mexican cartels push the drug over the Southwest border, hidden in anything from fake coconuts to lollipops. With supply booming in America, street heroin is now much purer: In Chicago, says DEA Special Agent Jack Riley, a standard bag of 2 to 3 percent pure heroin would have cost you up to $150 a decade ago. Today, you can get a bag of 7 to 10 percent purity for $10. That means users no longer have to inject heroin; they can smoke or snort it, increasing its appeal to users "who normally wouldn't come near it for fear of the needle," says Riley.

What's driving the demand?
America's increasing addiction to prescription pills, which give many people their first seductive taste of an opiate high. Doctors are freely prescribing opium-based painkillers such as OxyContin, Vicodin, and Percocet to people with orthopedic injuries and other physical pain, but some users don't stop when the prescription runs out. An estimated 6.8 million Americans abuse these pills, crushing them and snorting or injecting them to achieve a heroin-lite high. That's created a boom in black-market demand which, coupled with a federal crackdown, has caused prices to soar — pushing users toward heroin. With one oxycodone pill now costing about $30, and a glassine of heroin costing a sixth of the price, switching to "smack" (as users sometimes call the drug) is a "business decision," says Christian Moffitt, an addict interviewed by The Kansas City Star. Then, in 2010, the manufacturer of OxyContin deliberately changed the formula of its pills to make them more difficult to crush and snort, pushing even more opiate addicts toward heroin.

How deadly is heroin?
There was a 45 percent spike in the number of lethal overdoses between 2006 and 2010, to more than 3,000 deaths a year. The death toll has certainly grown since then. Unlike abusers of painkillers, heroin users never know the exact potency of the drug they're ingesting — or if it's been spiked with other strong opiates, such as the synthetic fentanyl, apparently responsible for at least 84 deaths along the East Coast in recent months. "[Users] think they're getting regular street heroin," said Thomas Carr, director of the Washington-Baltimore High Intensity Drug Trafficking Area, a public policy program. "Instead, they're getting something that could kill a horse."

Can anything be done to combat the epidemic?
The first step is cutting down on the overuse of prescription opiates. "Doctors need to break the habit of automatically writing refillable prescriptions for 20 or 30 Percocets for minor pain that will resolve in a few days," says addiction expert Keith Humphreys. Meanwhile, there's been a nationwide effort to equip first responders with a drug that can rescue heroin users from overdoses (see below), and at least 14 states have passed "Good Samaritan" laws granting limited immunity to witnesses of an overdose, so that they can call 911 without the fear of police involvement. "Most users don't want to die," said Karen Hacker, director of the Allegheny County Health Department in Pennsylvania. "They're not looking to commit suicide. They're looking to get high."

The antidote to overdoses
When someone dies from a heroin overdose, it's because the narcotic suppresses their essential functions so deeply that their body forgets to breathe. Their respiratory drive shuts down, their blood pressure drops, and their heart stops beating. A single drug, naloxone, can completely reverse these effects — if injected while the heat is still beating. "It's virtually 100 percent effective," said Wilson Compton, deputy director at the National Institute on Drug Abuse in Bethesda, Md. "If this medication is administered [properly], they wake up within a minute or two." More than 10,000 overdoses have been reversed in this way, and some New York police officers now carry a nasal-spray form of the drug. Last week, the Obama administration said it supported expanding naloxone's availability, so that first responders and family members can administer the drug during emergencies. "It's remarkable," said Compton. "You save their life."