Marijuana has long been called the gateway drug, supposedly opening kids’ minds to the wide world of illicit drugs — and their dangers. While the debate on whether marijuana causes that transition to other drugs will likely persist for some time, there is evidence that people who regularly use marijuana also tend to use other drugs as well. Seeking insight into why, researchers from New York University recently conducted a study to determine whether people use harder drugs for the same reasons they use marijuana.

The study, published in the American Journal of Drug and Alcohol Abuse, primarily looked at high school seniors’ reasons for smoking marijuana and how they related to other-drug use. In all, they looked at how marijuana use was associated with using eight other drugs: powder cocaine, crack, heroin, LSD, other hallucinogens, amphetamine/stimulants, tranquilizers/benzodiazepines, and narcotics outside of heroin.

“Aside from marijuana, a wide range of illicit drugs are prevalent, each having different use patterns, and different effects and dangers associated with use,” said Dr. Joseph J. Palamar, an assistant professor of population health at NYU Langone Medical Center and co-author of the study, in a press release. “Our research helped to identify subtypes of illicit marijuana users who use other drugs, as this may be able to inform prevention efforts.”

Palamar and his colleagues found boredom was among the most common reasons for using marijuana, with 31.3 percent of teens saying it was why they used it. These teens were also most likely to use powder cocaine or hallucinogens other than LSDmagic mushrooms, for example — for the same reason. “It appears that many students use marijuana as a form of sensation seeking to alleviate monotony, and our findings are somewhat consistent with other studies that have found that drugs such as cocaine and methamphetamine are also commonly used to alleviate boredom,” the researchers wrote.

Other reasons for marijuana use included for insight or understanding (19.8 percent), which was linked to a heightened tendency to use hallucinogens other than LSD, and to increase the effects of other drugs (11 percent). Though the researchers couldn’t acquire data on other drugs the teens were using together with marijuana, they suggested many people use cocaine while drinking alcohol, and ecstasy is often used in conjunction with drugs like ketamine.

The researchers also found teens who reported using marijuana to “experiment” were least likely to subsequently use harder drugs, especially prescription narcotics. It makes sense, considering they probably weren’t even sure about marijuana use — why try something with a stronger effect?

Researchers used data from 12 separate cohorts of the Monitoring the Future study to come to their results. Despite their findings, two-thirds of marijuana-using teens “did not report use of any other illicit drugs we examined,” Palamar said, adding that the research will help guide prevention efforts. “Programs and education efforts, for example, can benefit from knowing that marijuana users who use because they are bored are more likely to use certain other drugs. It may be feasible for prevention programs to address ways of coping with factors such as boredom in order to decrease risk.”

Source: Palamar J, Griffin-Tomas M, Kamboukos D. Reasons for recent marijuana use in relation to use of other illicit drugs among high school seniors in the United States. The American Journal of Drug and Alcohol Abuse. 2015.