Abstract
Risky sexual behavior and substance use appear to be interconnected behaviors among adolescents, but data are scarce regarding the extent to which sexual risk behavior is associated with high levels of marijuana and alcohol use, both separately and in combination. 301 adolescents were recruited from a short-term detention facility, and substance use and risky sexual behavior were assessed. We found that adolescents who frequently used marijuana, but not alcohol, reported significantly less risky sex as well as greater intentions to use condoms than either adolescents who frequently used alcohol, but not marijuana, or adolescents who frequently used both substances. Substance use status as a predictor of future risky sexual behavior followed a similar pattern. When designing interventions to reduce substance use in the context of risky sex, it might be especially effective to target efforts toward reducing harm associated with alcohol use, either alone or in combination with marijuana use.