Families in Society, Ahead of Print.
This study investigated the patterns of substance use initiation and transition across tobacco, alcohol, and illicit drugs over time using retrospective longitudinal data. Based on national data of 18,861 adolescents aged 14 to 17 years who had engaged in substance use, the findings revealed that nearly 50% of these adolescents initiated substance use with alcohol, 18% with tobacco, and 33% with illicit drugs. By the end of the second year, the probability of these adolescents trying a new substance class was 40% to 50%, rising to 80% to 90% by the eighth year. Adolescents who initiated with tobacco or illicit drugs exhibited a higher risk of transition. The study indicates the significant role of all substance classes in initiating adolescent substance use and highlights the rapidity of transitioning to new substance classes, underscoring the importance of proactive prevention and intervention strategies.