Heroin overdose deaths have sky-rocketed in recent years, quadrupling since 2000, U.S. health officials reported Wednesday.
At the same time, poisoning deaths related to painkiller abuse have levelled off, even dropping slightly in recent years, according to the report from the U.S. Centres for Disease Control and Prevention.
Prescription drug addicts are turning to heroin due to successful efforts to curb narcotic painkiller abuse, said Kelly Dunn, an assistant professor in the Behavioural Pharmacology Research Unit at Johns Hopkins University School of Medicine.
It's now harder to obtain prescription narcotics, thanks to improved tracking and regulation of the drugs, Dunn said. In addition, manufacturers have changed the formulation of painkillers to make them more difficult to abuse.
"Heroin's cheaper and easily available, and we're seeing increases in places that traditionally haven't had much heroin use," Dunn said. "Once people are dependent on prescription drugs, it's very rare for them to stop on their own with no treatment. If the drugs are suddenly less abusable, they will switch to something else that will alleviate withdrawal."
Read: Addicts switching from from painkillers to heroin
Overdose deaths have quadrupled
The CDC's National Centre for Health Statistics reports that between 2000 and 2013, the age-adjusted rate for overdose deaths involving heroin nearly quadrupled, rising from 0.7 deaths per 100,000 Americans in 2000 to 2.7 deaths per 100,000 in 2013.
One of the most recent high-profile deaths was that of actor Philip Seymour Hoffman, who died in February 2014 from a heroin overdose at age 46.
Steve Pasierb, president and CEO of the Partnership for Drug-Free Kids, noted that Hoffman had been in recovery for a long time. "Then he went back to using, and ended up dying from respiratory failure. Heroin is a respiratory depressant, and it shut down his respiratory system," Pasierb said.
Read: Why did Hoffman have to die?
Significant increase after 2010
The CDC researchers found that most of the increase in heroin deaths occurred recently - between 2010 and 2013. During that time, the United States experienced a 37 percent-per-year increase in heroin deaths, the study found.
Dr. Holly Hedegaard, an injury epidemiologist at the NCHS, said, "This increase has been what we've been hearing stories about, and now we can actually document it.
"There have been these anecdotes about increased heroin deaths, but until the 2013 data came out it was difficult for us to see what's been happening," she said.
While heroin deaths have soared, the death rates related to prescription narcotics have declined slightly, from 5.4 per 100,000 in 2010 to 5.1 per 100,000 in 2013, the CDC said.
The racial and ethnic background of people dying from heroin overdose also has shifted.
Blacks 45 to 64 were the group most likely to die from a heroin overdose in 2000. Today, whites aged 18 to 44 have the highest death rate from heroin abuse, the CDC said. The study also found that men were nearly four times as likely as women to die from a heroin overdose.
Read: Faces of addiction
Heroin was "waiting in the wings"
Overall, these numbers show that as policymakers made headway against prescription drug abuse in recent years, heroin was waiting in the wings as a ready-made substitute, Pasierb said.
"Heroin never went away," Pasierb said. "Today it's more cheap, more pure, more available than it's ever been."
Drug users can start heroin easily by sniffing it, but soon progress to smoking the drug and then injecting it, he said.
"Nobody ever thinks they're going to end up using a needle," Pasierb said. "There's no safe way to even dabble in heroin. It's one of the riskiest drugs out there, because of its addictive properties."
Heroin also is leaving its usual inner-city haunts and venturing into America's rural areas - another sign that prescription drug abusers are turning to heroin, Dunn and Pasierb said.
The CDC reports that the greatest increase in heroin deaths between 2000 and 2013 occurred in the Midwest, which experienced a nearly 11-fold leap in fatal overdoses.
The overdose rate quadrupled in the Northeast during that period, as heroin use trickled out of urban areas like Baltimore and New York City into the rural New England states, Dunn and Pasierb said.
"Vermont has been ravaged by heroin," Pasierb said. "The whole dynamic has changed. There's no place in America where heroin isn't available."
Heroin use in rural areas is difficult to combat, because those areas don't have the sort of treatment facilities that have - by necessity - sprung up in urban areas, Dunn said.
"Some rural patients will drive hours a day to get to a treatment centre for a single dose of methadone," she said.
Because treatment is not always available, officials need to step up efforts to distribute the medication naloxone across the nation, Dunn said. If given to overdose victims, naloxone can reverse the effects of heroin and save lives.
"Police and EMTs are starting to carry naloxone as a standard, so there's a greater recognition that this medication is needed," she said.
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