Adolescence and the transition to adulthood are characterized by heightened risks and opportunities. In documenting the natural history of youth alcohol and drug use, this chapter considers initiation of use and both normative and problematic use patterns. It is necessary to consider average developmental patterns across adolescence and young adulthood as well as variations in these patterns for unique subgroups. A developmental perspective highlights the importance of risk and protective factors and processes by which adolescents and young adults negotiate developmental transitions. These processes are important for understanding long-term consequences and for the prevention of substance use and misuse.
The 2010 Monitoring the Future national survey of high school seniors reported that 71% of adolescents had consumed alcohol by the 12th grade, 42% had tried cigarettes, 44% had used marijuana, and 25% had consumed an illegal drug besides marijuana. These rates suggest that substance use is a common but not universal experience during adolescence. Adolescence is a developmental period characterized by risk-taking behavior, and risk taking is heightened in adolescence for various reasons including biological development and identity exploration.