Teenagers are saying “no” to cigarettes, alcohol and other drugs of abuse, according to a survey, which also found that misuse of prescription pain medication remained high.

Scientists at the University of Michigan who have conducted the federally funded annual survey since the mid-1970s found that drug use in general has dropped a total of 19 percent over the past four years. High on the list of substances teens are less apt to touch: Cigarettes. Smoking rates among eighth-, 10th- and 12th-graders are at the lowest point since 1975.

“It is extraordinary,” said Dr. Nora Volkow, director of the National Institute on Drug Abuse, the federal agency that funds the survey. “This is great news. Our anti-drug campaigns are getting through.” She said the numbers suggest 700,000 more American teenagers are staying away from illicit drugs.

The researchers, led by Lloyd Johnston of Michigan’s Institute for Social Research, began surveying high school seniors and added eighth- and 10th-graders in 1991. They send out questionnaires annually to 50,000 teenagers in 400 schools around the country.

The teen brain is particularly vulnerable to drugs of abuse, said Dr. Herbert Kleber, a professor of psychiatry and director of the division on substance abuse at Columbia University Medical School. “The earlier a person starts, the more likely he or she is to continue doing drugs in later years.” Delaying drug use can prevent future drug abuse, he said.

But the annual survey also revealed that almost one in 10 teenagers continues to abuse prescription drugs. The survey recorded that 8.6 percent of teens misused amphetamines and 9.5 percent admitted using the powerful painkiller Vicodin. Many find such drugs in the family medicine cabinet or get them on the Internet.

The number of teenagers abusing prescription drugs has not increased, but levels are high and remain the same as last year, NIDA’s Volkow said.

“Clean your cabinets of all medicines that have abuse potential,” she said. “Parents are the first line of defense. Be alert to any behavioral changes in your children.”

In 2002, the researchers began asking students about the highly addictive prescription painkiller OxyContin. That year, 4 percent of 12th-graders said that they had tried OxyContin. This year, the rate climbed to 5.5 percent.

In the survey, teenagers are asked about their use of drugs, tobacco and alcohol in the preceding month and year. Lifetime use of cigarettes declined 2 percent among eighth-graders, 1.7 percent among 10th-graders, and 2.8 percent among seniors, according to the survey.

Alcohol use was down from the previous year by 2.7 percent among eighth-graders, 1.5 percent among 10th-graders and 2.1 percent among 12th-graders. Methamphetamine use showed similar declines, as did steroid use. Marijuana use was also down.