Marijuana: use among young males and health outcomes.

Marijuana is the most commonly used illicit drug by adolescents and young adults, with more males than females reporting marijuana use. The adolescent and young adult years represent a critical period for interventions to prevent marijuana use and abuse. This article reviews relevant literature, including trends in young males' marijuana use and health effects of marijuana use. By most measures, there has been little net change in marijuana use among 12th graders and young adults since the 1990s. Despite males' greater use, little research has examined gender differences in areas such as metabolism of marijuana and long-term impact of marijuana use. In many areas, including dental health, fertility, and respiratory function, research is either sparse or has yielded conflicting results. Similarly, research on marijuana's carcinogenic effects has yielded conflicting results; however, a small but consistent literature indicates that marijuana use is linked to cancers unique to males. A stronger literature has identified an association between marijuana use and psychiatric problems. Clinical and program interventions for adolescents have potential to prevent marijuana use, as well as screen for and treat marijuana abuse. Improved research is needed, such as research with greater consistency in defining levels of use and greater emphasis on gender differences. Such research would help clinical and program interventions focus on those most at risk for adverse outcomes.