Explainer

What’s in “Bad Heroin”?

The mysterious drug cocktail that may have killed Philip Seymour Hoffman.

Philip Seymour Hoffman
Philip Seymour Hoffman arrives for a screening of The Master during the Venice Film Festival on Sept. 1, 2012.

Photo by Tiziana Fabi/AFP/Getty Images

Actor Philip Seymour Hoffman was found dead in his Manhattan apartment on Sunday. The cause of death is presumed to be a drug overdose, possibly involving a batch of so-called “bad heroin” that has caused problems on the East Coast. Is there a novel form of deadly heroin on the street?

Not really. Authorities in several states have sent out “contaminated heroin” alerts in recent weeks. The problem batches contain the prescription narcotic fentanyl, either mislabeled as heroin or mixed with heroin and sold under a brand name such as “magic,” “Theraflu,” or “Bud Ice.” Fentanyl is closely related to heroin but cheaper and between 50 to 80 times more potent, making it an appealing substitute for drug dealers and users. Many drug-screening tests fail to detect fentanyl, because its concentration in a user’s urine is typically lower than that of heroin.

The fentanyl-heroin cocktail is nothing new; the combination has been available on the street since the 1970s. Fentanyl abuse kills dozens of people annually, often because users apparently misjudge the strength of a dose. We do appear to be experiencing a surge in fentanyl-related deaths right now—22 people are believed to have died from these contaminated heroin supplies in six Pennsylvania counties alone. Such outbreaks seem to occur every few years, as drug suppliers find a prolific and cheap source of fentanyl or this particular drug cocktail gains popularity on the street.

The most significant outbreak of fentanyl-related deaths came in 2005–2006, when nearly 1,000 people died from fentanyl nationwide. The outbreak was of particular concern to drug-control authorities because it happened on a national scale. (Most fentanyl death waves are localized.) The vast majority of the street fentanyl was eventually traced to a single factory in Toluca, Mexico. When Mexican authorities raided the factory in May 2006, the death rate from fentanyl quickly returned to background levels. It isn’t yet clear whether the current increase in fentanyl-related deaths is traceable to a single source or whether the illicit manufacture of the drug has diversified in response to law enforcement pressure.

Fentanyl appears to be a favorite mixer among drug dealers and abusers, as authorities have also seized mixtures of the prescription drug with cocaine. The ratio of the drugs in the cocktail varies widely, which is one of the reasons these combinations are so dangerous—the user doesn’t know exactly what he’s taking. Some packets of cocaine contain just trace amounts of fentanyl, while others are up to one-quarter fentanyl. Heroin-fentanyl mixtures often include as much as 50 percent fentanyl.

See more of Slate’s coverage of Philip Seymour Hoffman.

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