"The average age of onset of use of the different substances which was recorded in 2011 remained stable, generally speaking, compared to the year before. The substances shown as being used for the first time at a younger age are those showing the highest prevalence figures, in other words, tobacco and alcoholic beverages (16.5 and 16.7 years of age, respectively). Regarding illicit substances, the substance showing the youngest age of onset of use continues to be cannabis, the age of onset being 18.7 years of age. The greatest change in the age of onset of use compared to 2009 is for heroin, given that the age dropped from 22.9 years of age to 20.7 years of age in 2011. Apart from the above, the substance showing the oldest age of onset is that of the hypnosedatives (34.5 years of age), although this age drops to 27.8 years of age regarding non-prescription hypnosedatives. In this regard, from an overall standpoint, the age of onset of the use of the different drugs is within the 16-21 age range (Table 2.6 and Fig. 2.1)."

Source

Government Delegation of National Plan on Drugs (Reitox National Focal Point for Spain), "2012 National Report (2011 Data) to the EMCDDA: Spain: New Development, Trends and in-depth information on selected issues" (Madrid, Spain: DGPNSD, Dec. 2012), p. 30.
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