"A number of other substances with hallucinogenic, anaesthetic, dissociative and depressant properties are used in Europe: these include LSD (lysergic acid diethylamide), hallucinogenic mushrooms, ketamine and GHB (gamma-hydroxybutyrate).
"The recreational use of ketamine and GHB (including its precursor GBL, gamma-butyrolactone) has been reported among subgroups of drug users in Europe for the last two decades. Where they exist, national estimates of the prevalence of GHB and ketamine use in both adult and school populations remain low. In their most recent surveys, the Netherlands reported last year prevalence of GHB use at 0.4% for adults (15–64) and Norway at 0.1% (16–64), while and Romania reported 0.5% for young adults (15–34). Higher levels of both GHB use and related problems have been reported among particular social groups at the city and local level in some countries, including the Netherlands, Norway and the United Kingdom. Last year prevalence of ketamine use among young adults (15–34) was estimated at 0.3% in Denmark and Spain, and the United Kingdom reported last year ketamine use at 1.6% among 16- to 24-year-olds, a stable trend since 2008.
"The overall prevalence levels of LSD and hallucinogenic mushroom use in Europe have been generally low and stable for a number of years. Among young adults (15–34), national surveys report last year prevalence estimates of less than 1% for both substances, with the exception of Finland with a prevalence of 1.3% for LSD, and for hallucinogenic mushrooms the United Kingdom (1%), the Netherlands (1.3%), Finland (1.9%) and the Czech Republic (2.3%)."