The death of actor Philip Seymour Hoffman from an apparent overdose of heroin has, like the death of "Glee" star Cory Monteith, highlighted the resurgence in use of a narcotic that once seemed to be fading away.
The number of heroin users in the U.S. nearly doubled in five years, to 669,000 in 2012 from 373,000 in 2007, according to statistics from the Substance Abuse and Mental Health Services Administration. The number who abused or grew dependent on heroin more than doubled in 10 years to 467,000 in 2012 from 214,000 in 2002.
Those numbers coincide with trends for drug-induced deaths. In November, the Centers for Disease Control and Prevention's (CDC) Morbidity and Mortality Weekly Report declared that "deaths from drug overdose have increased sharply in the past decade," claiming 40,393 people in 2010.
"Up here in the Cleveland area, we are going through an epidemic of heroin," Dr. Jason Jerry, a psychiatrist and addiction medicine expert at the Cleveland Clinic's Alcohol and Drug Recovery Center told NBC News.
Heroin is not just in urban areas, either. Small towns, like Lancaster, Ohio, about 25 miles southeast of Columbus have seen a spike in heroin use and related arrests. In Ohio's Fairfield and Hocking counties, which have a combined population of 172,000, police seized 8,208 unit doses of heroin last year, compared to 1,432 unit doses in 2012.
Traci Green, an assistant professor of emergency medicine and epidemiology at the Warren Alpert Medical School of Brown University said drug overdose deaths in Rhode Island — mostly from opiates including heroin — during the first 13 days of 2014 were double the same period last year, and that the deaths were spread all over the state.
In the past, Green said, people have used more prescription opiates either legitimately, as prescribed for pain, or illicitly to get high. But in recent years, government crackdowns on illicit use of pain medications has made pills more expensive and harder to get. "And heroin is making its way into all these places," Green told NBC News.
According to law enforcement sources, about 50 bags of heroin, some used, some not, along with numerous syringes and addiction treatment medication were found in Hoffman's apartment.
If true, those items could be a sad tableau depicting the struggles of addicts trying to stay free of a drug like heroin.
As an opiate, heroin is one of the most addictive substances known. It triggers receptors in the brain's reward regions, those parts of the brain that teach us that food, sex and warmth are desirable so we'll survive.
"The problem is that drugs hijack that circuit," Jerry said. "Rather than the contextual enjoyment you get from a nice meal, or sex, drugs activate that circuit directly and bypass the context so they have a much more powerful effect."
The brain eventually accommodates this drug use, leading to physical changes in the brain and dependence. Users no longer enjoy they drug — they need it.
Hoffman was candid about struggles with drug addiction and said in interviews last year that after 23 years sober, he fell off the wagon and relapsed, leading to rehab. Hoffman's friends have been quoted as saying that he seemed free of drugs after emerging from rehab.
But drug addiction is a chronic disease that can flare again for any number of reasons, like stress or even a visual cue reminding a former addict of the drug.
"The 28-day rehab model, lots of out-of-pocket expenses, flying to a fancy place to get detoxed and coming home, all too often is a recipe for disaster," Jerry said. Statistics show that only about 10 to 20 percent of such patients maintain long-term abstinence.
A program akin to 12-step counseling with ongoing support, combined with anti-addiction drugs like methadone and suboxone produce much better results. (It was not immediately clear which anti-addiction drugs were found in Hoffman's apartment.)
When an addict does begin to use again, he or she is especially vulnerable to an overdose. By the time most addicts seek help the first time, they've developed a tolerance for the drug and may be using a dose that would kill a first-time user. When first starting to use again, a relapsing addict may return to that same dose, but now it could fatal.
In recent years, another danger has popped up. Heroin laced with the powerful anesthetic fentanyl, or fentanyl simply labeled as heroin, has killed hundreds of people.
Last spring, the CDC conducted an investigation into a sudden spike of overdose deaths in Rhode Island. It found a cluster of 12 deaths in people aged 19 to 57 attributable to a synthetic version of fentanyl called acetyl fentanyl which is much more potent than heroin.
Though acetyl fentanyl has no legitimate pharmaceutical use and is not available by prescription anywhere, similar reports of fentanyl-related deaths have occurred around the country. "We had, I believe, about 20 ODs in a 12-hour period, back in November," Jerry said.
Heroin users may be unaware their drugs have been laced with fentanyl. A study by researchers from the New Jersey Department of Health Services and Rutgers University linked declining heroin purity to added fentanyl in illegal drug markets along the east coast.
Reports have stated that bags of heroin in Hoffman's office were stamped "Ace of Spades" and "Ace of Hearts." It was too soon Monday to know if the heroin Hoffman injected was tainted.