They are perhaps best known for their youthful indulgence in an exotic menu of illicit substances such as Acapulco Gold, windowpane acid, mescaline and Quaaludes.

Now, experts warn, the 78 million-strong baby boomer generation is bringing its propensity to use pills and pot to its senior years. In what researchers call the tip of an ominous trend, boomers are responsible for a spike in drug and alcohol abuse that is expected to mushroom in coming years.
"I think it's a silent, unappreciated problem that has the potential to tarnish the baby boomers' golden years," said Dr. Bruce Henricks, medical director of the Mutual of Omaha insurance company.

One of the few comprehensive studies of the problem found that 3 million Americans older than 50 in 2004 had used illicit drugs such as marijuana, cocaine or heroin, or had misused anti-anxiety, anti-depression or other prescription drugs. Research by the federal Substance Abuse and Mental Health Services Administration estimates that number could more than double by 2020.

The drug-abuse toll is evident. Hospital emergency rooms reported treating more than 400,000 boomer-aged patients for drug overdoses in 2004, according to the federal Centers for Disease Control and Prevention. Many do not make it, as was reflected in a recent Scripps Howard analysis that determined that boomers made up about half of all people nationwide who died of drug-related causes in 2003 -- most from overdoses.

A similar state health services department survey in California, where the counterculture first blossomed 40 years ago, found a nearly 30 percent increase in boomer drug deaths between 2000 and 2004. In Arizona, officials counted 250 boomers dead of drug-related causes in 2005, compared with 39 in 1995.