L’observation des usages de drogues à l’adolescence est une priorité des pouvoirs publics qui nécessite la mise en oeuvre de méthodes adaptées à ce sujet sensible. Après avoir resitué les outils de surveillance épidémiologique parmi les différents outils de sciences sociales disponibles, ce travail synthétise les résultats des enquêtes représentatives de la population adolescente et les principales évolutions observées ces dernières années. Une enquête auprès des adolescents de 17 ans et une autre menée en population générale dont l’exploitation concerne ici les 18-25 ans ont été considérées. Une enquête scolaire menée auprès des 12-18 ans permet par ailleurs une mise en regard avec les autres nations européennes. La diffusion des usages de produits psycho-actifs durant l’adolescence est rapide, avec toutefois des nuances importantes suivant les produits. Depuis 2000, le tabagisme est en net recul, tandis que les usages d’alcool sont relativement stables et les ivresses apparaissent en hausse entre 2003 et 2005. La hausse de l’expérimentation du cannabis et de ses usages réguliers, très forte au cours des années 1990, a cessé au cours des années 2000. Enfin, si l’ecstasy et la cocaïne se sont diffusées dans la population, leurs niveaux d’expérimentation restent faibles et ceux des autres produits, qui apparaissent stables, sont encore moins fréquents.

Epidemiological monitoring of drug use among adolescents or young adults is a major concern for public policy makers. This surveillance requires the use of adapted methodological solutions. This article presents how far epidemiological surveillance is a useful tool for monitoring drug use at adolescence. It also presents the results of the French general population surveys among adolescents or young adults, and the trends in the last decade. It relies on a survey among 17 years old adolescents and a general population survey among adults (analysis is restricted to people aged 18-25). A European school survey among 16 years old is also presented to compare the French situation to other European countries levels of use. The use of psychoactive substance increases fast with age during adolescence however results vary from one substance to another. Since year 2000, tobacco use is decreasing when alcohol use frequency appears stable between 2003 and 2005, although drunkenness has increased from 2000 to 2005. The frequency of lifetime or occasional use of cannabis appears stable since 2000. Among 17 years old, the proportion of regular users of cannabis has been stable between 2000 and 2005. Finally, the prevalence of ecstasy and cocaine increased during this period of time, despite being less than 4%, but the levels of the other illicit substances are low and stable. The results on alcohol variables and tobacco use in France are rather close to the European average. Four out of five 16 years old students had drunk alcohol during the past 12 months and 36 percent had been drunk during this period (vs 39% in the average European country). About one-third of the students had smoked cigarettes during the past 30 days (close to the 29% in the average European country). The use of cannabis, however, is clearly more prevalent in France. Almost one-third (31%) of the students had already used cannabis (vs 19% in the average European country). The use of inhalants was reported by 12 percent, which is close to the average, while 15 percent of the students had used tranquillisers or sedatives without a doctor’s prescription, which is more than twice the European average (6%).