[The consumption of psychoactive substances by adolescents in schools in Ribeiräo Preto, SP (Brazil). I--Prevalence of consumption by sex, age and substance].

INTRODUCTION

Concern over the consumption of psychoactive substances by teenagers has given rise to a great worldwide effort to produce information about this phenomenon. This study set out to investigate the prevalence of consumption of legal and illegal psychoactive substances, its distribution by age, sex and age at first experience of them, among teenage pupils in county, Ribeirão Preto, SP, Southeastern Brazil.

MATERIAL AND METHOD: A self-applicable questionnaire duly adapted and submitted to a reliability test was applied to a proportional sample of 1,025 teenagers enrolled in 8th, 9th, 10th and 11th grades at public and private city schools. The questionnaire contained questions about the use of ten classes of psychoactive substances, demographic questions and validation information, as well as questions about the perception and intrinsic behavior related to drug consumption.

RESULTS

The sample of 88.9% had consumed alcoholic beverages sometime in their lives, 37.7% had used tobacco, 31.1% solvents, 10.5% medicines, 6.8% marihuana, 2.7% cocaine, 1.6% hallucinogens, and 0.3% of the sample had consumed some opiate substance. The rates of consumption increased with age for all substances; however, the use of tobacco and of illegal substances was less intense during the later years of adolescence. As to sex distribution, boys consumed more than girls, except for medicines, with girls consuming barbiturates, amphetamines and tranquilizers in proportions similar to or higher than those observed among boys. Age at first experience showed that access to psychoactive substances occurred at very early ages.

CONCLUSIONS

Experimenting with psychoactive substances, whether legal or illegal, is a frequent phenomenon during adolescence, both among boys and girls, often at very early ages.