New York ? About one in five teenagers has tried prescription painkillers such as Vicodin and OxyContin to get high, with the pill-popping members of “Generation Rx” often raiding their parents’ medicine cabinets, according to a study by the Partnership for a Drug-Free America.

The 17th annual study on teen drug abuse, released Thursday, found that more teens had abused a prescription painkiller in 2004 than Ecstasy, cocaine, crack or LSD. One in 11 teens had abused over-the-counter products such as cough medicine, the study reported.

“For the first time, our national study finds that today’s teens are more likely to have abused a prescription painkiller to get high than they are to have experimented with a variety of illegal drugs,” Partnership Chairman Roy Bostock said. “In other words, Generation Rx has arrived.”

According to the study, the most popular prescription drug abused by teens was Vicodin, with 18 percent — or about 4.3 million youths — reporting they had used it to get high. OxyContin and drugs for attention-deficit disorder such as Ritalin/Adderall followed with one in 10 teens reporting they had tried them.

Fewer than half the teens — 48 percent — said they saw “great risk” in experimenting with prescription medicines. “Ease of access” was cited as a major factor in trying the medications.

It was only the second year that the survey had studied abuse of legal drugs.

For the first time, the 2004 survey included a question about the use of over-the-counter products to get high. Nine percent, or about 2.2 million teens, had experimented with cough syrup and other such products.

It also found that the number of teens reporting marijuana use declined to 37 percent last year, compared with 42 percent a half-dozen years earlier. Over the same amount of time, Ecstasy use declined from 12 percent to 9 percent.