Marijuana use continues to be on the upswing in the United States. A public relations campaign claiming health benefits while ignoring health risks have led to diminishing public disapproval and more lenient legislation.

People who disapprove of a particular drug are unlikely to use it, but what about the gateway affect? Does the use of one drug affects people's attitudes toward using other drugs? Do personality traits matter?

High school seniors who frown upon the use of drugs are most likely to be female, nonsmokers or hold strong religious beliefs, according to a paper by Joseph Palamar of New York University. Palamar that examines how teenagers' attitudes toward marijuana influenced their thoughts on the further use of other illicit drugs. 

Palamar examined how demographics and a lifetime use of various drugs – marijuana use in particular – can predict if a person will become partial to using "harder" and more dangerous drugs, such as powder cocaine, crack, LSD, heroin, amphetamine and ecstasy, also known as "Molly." Data was obtained from 29,054 high school seniors who took part in the Monitoring the Future annual cross-sectional survey of approximately 130 public and private schools in 48 states between 2007 and 2011.

Palamar found that youths who smoked cigarettes or used more than one "hard" drug were consistently less critical of other drug use. The lifetime use of alcohol had no impact on people's attitudes. Those who used only marijuana tended to be less judgmental of further using such so-called "socially acceptable" drugs as LSD, amphetamine and ecstasy. They did not approve of cocaine, crack or heroin, however, most likely because of their perceived dangers and addictive qualities.

Unsurprisingly, female high school seniors consistently disapproved of using cocaine, crack, LSD and ecstasy. Compared to their male counterparts, females are generally less likely to use most drugs. Palamar was also not surprised by the finding that religiosity robustly increased attitudes against drug use, as it is a major force in societal values.

Youths from more advantaged socio-economic backgrounds with highly educated parents as well as those living in urban areas were much less disapproving of the use of the so-called "less dangerous" drugs. Palamar believes that the higher prevalence of illicit drug use in urban areas may be helping to normalize drug use in cities.

The finding that Black students are less disapproving of powder cocaine, crack and ecstasy is somewhat paradoxical as members of this group generally use such drugs less than White students do. This could, in part, be explained by their strong religious beliefs and the higher rates of arrests and incarceration among Blacks that may serve as a deterrent. The normalization of ecstasy, specifically in rap and hip-hop music, may explain why Black youths are less disapproving of it.

"Public health and policy experts need to ensure that the use of other drugs does not increase in light of the growing prevalence of marijuana use and more lenient policies surrounding it," Palamar explains. "Although it may be difficult to prevent an adolescent or a young adult from using alcohol, tobacco or marijuana, we need to prevent individuals from becoming users of multiple drugs."

Citation: Palamar, J.J. (2013). Predictors of Disapproval towards “Hard Drug” use among High School Seniors in the US, Prevention Science DOI 10.1007/s11121-013-0436-0