Medical marijuana legalization and associated illicit drug use and prescription medication misuse among adolescents in the U.S.

BACKGROUND

Use of illicit drugs and misuse of prescription medications among U.S. adolescents have been major public health issues. As over half of the states have implemented medical marijuana laws (MMLs), it is unclear if MML implementation is associated with use of illicit drugs and misuse of prescription medications among adolescents.

METHODS

This study used data from the 2013-2014 National Survey of Drug Use and Health and included adolescents aged 12-18 with a total of 26,826 participants after the propensity-score matching used to reduce selection bias between states that had and had not implemented MML. Seven logistic regressions were conducted to examine MML implementation and associated use of illicit drugs (including cocaine/crack, heroin, hallucinogens, and inhalants) and misuse of prescription medications (including pain relievers, tranquilizers/sedatives, and stimulants), controlling for sociodemographics and use of cigarettes, alcohol, and marijuana.

RESULTS

Adolescents residing in the states that had legalized medical marijuana were more likely to use cocaine/crack and heroin in the past 12 months (OR = 1.63, 2.61, respectively; both ps < 0.05). However, MML implementation was not associated with the likelihood of using other illicit drugs or misusing prescription medications.

CONCLUSIONS

The study findings suggest that for the states that have implemented MML, policy and educational interventions should as well be implemented to prevent not only marijuana use but also use of other harder drugs such as cocaine/crack and heroin among adolescents. States that have yet implemented MML should consider the possible associations between MML implementation and use of other illicit drugs when legislating MML.