Objectives: After several years of increasing 'normalisation' of cannabis use in Switzerland at the
beginning of the new millennium, a reversed tendency, marked among others by a more stringent
law-enforcement, set in. The presentation examines the question of where adolescents and young
adults obtained cannabis, within the context of this societal change. In addition, it compares the
sources of supply for cannabis with those found in studies of other European countries.
Methods: Analyses are based on data from the Swiss Cannabis Monitoring Study. As part of this
longitudinal, representative population survey, more than 5000 adolescents and young adults
were interviewed by telephone on the topic of cannabis. Within the total sample, 593 (2004) or
554 (2007) respectively, current cannabis users replied to the questions on sources of supply.
Changes in law-enforcement and societal climate concerning cannabis are assessed based on
relevant literature, media reports and parliamentary discussions.
Results: Whereas 22% of cannabis users stated in 2004 that they bought their cannabis from
vendors in hemp shops, this proportion drastically decreased to 6% three years later. At the same
time, cannabis was obtained increasingly from friends, while the proportion of users who
purchased cannabis from dealers in the alleyway, more than doubled from 6% (2004) to 13%
(2007). It was male cannabis users, and in particular, young adult and frequent users, who have
moved into the alleyways. Generally, users who buy cannabis in the alleyway show more
cannabis-related problems than those who mainly name other sources of supply, even when
adjusted for sex, age and frequency of cannabis use.
Discussion: Possible consequences of these changes in cannabis supply, like the risk of merging a
previously cannabis-only market with other 'harder' drugs markets, are discussed.