Methadone emerges as new killer

The drug, which comes in pill or liquid form, recently has come under scrutiny in the death of former Playboy model Anna Nicole Smith. A doctor in Studio City prescribed methadone to Smith for pain treatment before she was found dead Feb. 8 in her Hollywood, Fla., hotel suite.

A coroner has yet to determine her cause of death, and the doctor said his treatment was "medically sound and appropriate."

Months earlier, Smith's 20-year-old son died in the Bahamas after taking a lethal mixture of methadone and two antidepressants, Zoloft and Lexapro.

Well before these deaths, however, drug counselors and clinicians were concerned about increased abuse of the drug on the streets, in group homes and even in middle schools.

It is an ironic turn in the history of methadone, which for years has been used to treat heroin addiction.

A synthetic opiate, methadone is similar to heroin in chemistry, curbing a user's craving for the illegal opiate by blocking the sensors that heroin stimulates without producing a heroin high.

In recent years, methadone has proved lethal to a growing number of patients or addicts who use it in conjunction with prescription drugs including Valium, Xanax or, in the case of addicts, illegal narcotics such as cocaine.

Sometimes users swallow methadone before or after they "puff," when they seek to get high by slowly inhaling the chemicals from an aerosol can.

"Every year, we see hundreds of these deaths, and the numbers continue to increase," said Bruce Goldberger, director of toxicology at the University of Florida, who has been at the forefront of tracking methadone-related deaths. "It is absolutely the fastest-growing drug problem."

A federal government study found that nationwide methadone-related deaths climbed to more than 3,800 in 2004 from about 780 in 1999. Among all narcotic-related deaths in 2004, only cocaine killed more people in the United States than methadone.

Physicians and others point out that methadone's potential for abuse isn't as high as that of opiates like heroin because it does not induce a strong euphoria on its own.