Objective: To estimate the association of parental drunkenness and parenting style with alcohol consumption among adolescents and the contributions of parental drunkenness and parenting style to the prevalence of binge drinking among adolescents. Method: Cross-sectional survey of a representative sample of secondary students aged 13 to 18 from 27 Brazilian state capitals (n=17,028). Private and public schools were included. A self-report questionnaire collected data on adolescents’ alcohol drinking behavior, parenting styles, and parenting and peer models of drunkenness. Results: Non-authoritative parenting style and parental drunkenness are associated with binge drinking among adolescents. Authoritarian, indulgent, and negligent parenting styles were associated with 1.50-, 2.51-, and 2.82-fold increases in prevalence of adolescent binge drinking, and parental drunkenness, with a 1.99-fold increase. The non-authoritative parenting style made a larger contribution than parental drunkenness to adolescent binge drinking. Conclusions: Non-authoritative parenting style and parental drunkenness seem to play an important role in adolescents’ binge drinking behavior. At the population level, parenting style appears associated with a greater contribution to this behavior among adolescents. Prevention strategies targeting parental drunkenness may be bolstered if a broader approach including parenting styles is in place.

Objectives: To describe patterns of nonprescribed use of tranquilizers by students aged 10 to 18 years and assess the sociodemographic characteristics of these adolescents and their use of other substances. Methods: A randomized and stratified sample of 47,979 students from state and private schools of the 27 Brazilian state capitals completed a self-report questionnaire. Poisson regression was used to estimate the associations between tranquilizer use and sociodemographic factors, as well as the use of other psychotropic substances. Results: The lifetime prevalence of nonprescribed use of tranquilizers was 3.9%. Use was most common among girls, wealthier adolescents, and those from private schools. An association was found between use of tranquilizers and lifetime use of alcohol (prevalence ratio [PR] = 3.15; 95% confidence intervals [95%CI] 2.58-3.85), tobacco (PR = 2.61; 95%CI 2.31-2.95), illicit drugs (PR = 3.70; 95%CI 3.19-4.29), and other prescription drugs (PR = 7.03; 95%CI 6.18-7.99). As the number of substances adolescents reported having used increased, so did the nonprescribed use of tranquilizers. Conclusions: Nonprescribed use of tranquilizers by adolescents might indicate the use of other substances, including high-risk combinations such as tranquilizers and alcohol. The risks of this association should be addressed during the early stages of drug prevention programs.