A transversal study on consumption of medicines was performed in 1,020 children and adolescents (10 to 21 years; mean age 15.3 years) questioned at school. 60.2% used at least one medicine during the week before the study. The mean number of used drugs was 2 by each consumer. There was no increase in drug consumption according to the different classes of age (10 to 14, 15 to 17, 18 to 21 years). However, from 15 years old, girls used more drugs than boys. The most used medicines are neuropsychotropic drugs (analgesics or psychostimulants). Prescription from non medical origin (self-medication or prescription by parents) was found in 46.1% of subjects. Some factors are significantly corelated with a more marked consumption of medicines: familial or personal problems in the whole population, social class of parents in the population aged from 10 to 14 years, regular use of medicines by other members of the family for adolescents from 15 to 17 years.