Teens are shunning synthetic marijuana, such as K2 and Spice, but smoking more of the real thing, a national survey of more than 40,000 children in three grades found.
The number of high school seniors who said they used the synthetic drugs dropped sharply from 11% in 2012 to 8% in 2013, the Monitoring the Future survey, released Wednesday, found. A growing number of teens see the drugs as dangerous.
Perceptions of marijuana have slid in the other direction as fewer teens see the drug as harmful and more smoke it. In 2013, one in 15 seniors reported using marijuana daily, up from one in 50 in 1993, the survey found.
Monitoring the Future, funded by the National Institute on Drug Abuse and conducted by researchers at the University of Michigan, has surveyed high school seniors since 1975. The survey added eighth- and 10th-graders in 1991. Investigators surveyed 41,675 students in 389 public and private schools.
Teen marijuana use began increasing in 2008 after a decade of decline. About 40% of high school seniors see smoking marijuana as risky, down from 44% last year and 75% nearly two decades ago. Historically, when teens perceive marijuana as safe, use rises, lead researcher Lloyd Johnston said.
"Young people are getting the wrong message from the medical marijuana and legalization campaigns," Gil Kerlikowske, director of National Drug Control Policy. "If it's continued to be talked about as a benign substance that has no ill effects, we're doing a great disservice to young people by giving them that message."
About one in four seniors reported smoking marijuana in the month before taking the survey and 36% reported smoking in the past year. Among sophomores, 30% had smoked in the past year and 18% in the past month and 4% daily. About 12% of eighth-graders smoked marijuana in the past year.
NIDA Director Nora Volkow said marijuana use at a young age can alter brain development and increase the risk for addiction.
"The children whose experimentation leads to regular use are setting themselves up for declines in IQ and diminished ability for success in life," Volkow said.
Marijuana's popularity varies over the years for many reasons, said Ethan Nadelmann, executive director of the Drug Policy Alliance, which favors legalization of the drug.
"But it's important to keep in mind that marijuana pales in comparison to alcohol, cigarettes, inhalants and pharmaceutical drugs in terms of dangers to young people," Nadelmann said. "Indeed for many young people, the worst consequences of marijuana involve arrest for marijuana possession, not its consumption."
In 2013, students who reported using illicit drugs rose slightly over last year. Among eighth-graders, 15% said they had used drugs in the past year. Nearly a third of 10th-graders (32%) and 40% of 12th-graders reported using drugs during the past year. The most popular drug is marijuana.
The survey added a question about synthetic marijuana in 2011 as reports of children sickened by the drugs emerged. Synthetic marijuana, made by spraying herbs with chemicals that mimic the marijuana, was the second most widely used illicit drug among 10th- and 12th-graders in 2012 after marijuana, the survey found.
Less than 1% of teens surveyed said they used the synthetic hallucinogen known as "bath salts." In all three grades, the number of students who say using "bath salts" is very risky increased sharply. The percentage of seniors who indicated occasional use of bath salts is harmful rose 25%, a steep rise in a short time that the researchers say is uncommon.
"Unlike synthetic marijuana, which experienced a substantial rise in popularity after entering the scene, use of bath salts has remained quite contained, suggesting that the messages about its dangers have been received," the survey analysis said.
Smoking, drinking and getting high on prescription painkillers continued to decline in 2013, the survey found. Fewer than 10% of teenagers reported smoking in the past month, down by two-thirds from its peak in 1997. Among seniors, who have the highest rates of cigarette smoking, the number of regular smokers decreased from 17% in 2012 to 16% in 2013.
Alcohol use continued its two-decade decline, hitting record lows in 2013, the survey found. Binge drinking also dropped about 2% among 10th- and 12th-graders.
"We've had some very intensive and aggressive prevention campaigns for alcohol and tobacco that have been successful," Volkow said.