According to the last survey by the World Health Organization about adolescent behaviour (Health Behaviour in School-aged Children)- based on a study carried out in 42 countries, mainly European, in 2013 and 2014- Spanish teenagers are among the heaviest cannabis consumers.

Concerning the Spanish Survey on Drug Use in Secondary Schools (ESTUDES 2016-17, National Plan on Drugs) it has to be mentioned that 170 000 14- to 18- year- old students started taking cannabis, a similar figure as for the cigarettes (184 600).

About 18.3 per cent of 14-to 18-year-old students in Spain have recognized that they have consumed the before mentioned substance during the last 30 days, which would mean that a total of 61 810 people of this age bracket has a problematic consumption according to classifications (CAST≥4).

The growing consumption is associated with an earlier initiation into drug use. It is outlined that this earlier initiation leads to a greater risk of problematic consumption, a subsequent use of other illicit drugs, together with diverse alterations of cognitive processing and motor function, aggravation of the psychopathological symptoms in adulthood and increased probability of school failure.

As many other addictive substances, the aetiology of cannabis consumption among teenagers, temporary or problematic, has different causes. Individual, family and school risk factors, as well as environmental influences have already been reported, although an interdisciplinary approach about consumption and consumers is still required.

Additionally, the large majority of cannabis consumers roll tobacco and hashish together (or marihuana occasionally). Jointly consuming both substances have only recently become apparent and outlined (EVICT report, 2016).