Consequences for The Use of Highly Addictive Drugs
Adolescent cigarette smoking in the United States has decreased dramatically over the past two decades, with the percentage of 17-year-olds who have ever smoked a cigarette dropping from 63% to 24%. This decline acts as a natural experiment to test competing predictions about how a decrease in cigarette smoking will affect adolescent use of other addictive drugs. On the one hand, the "gateway" theory predicts a decline in adolescent use of other addictive drugs. It builds on the observation that drug use typically follows a sequence in which use of cigarettes precedes use of other addictive drugs. Consequently, fewer youth initiating this sequence should result in fewer youth progressing to use of other drugs. On the other hand, the "liability" theory predicts an increase in use of other addictive drugs. It posits that some adolescents have a high propensity for general drug use, and these adolescents who do not smoke will instead switch to use of other drugs, which consequently will increase in prevalence. To examine these competing predictions we examine the outcomes of adolescent use of marijuana, amphetamines, tranquilizers, and opioids. Results differ by outcome.