The prevalence of use of illicit substances in Spain has been relatively stable over the last few years, with approximately one third of the adult population reporting lifetime use of an illicit substance. Cannabis, followed by cocaine, is the most commonly used drug, with use mainly concentrated among adolescents and adults younger than 35 years. However, the latest available data from a 2015 general population study confirm that the prevalence of use of both substances has declined in the last 10 years.
The use of all illicit substances remains more prevalent among males than females.
The prevalence of the use of new psychoactive substances (NPS) has remained stable since 2011, with about 3.4 % of adults in the 2015 study reporting ever having used NPS. Most NPS users are young males with patterns of experimental polydrug use. In general, polydrug use remains a very common consumption pattern, especially among those aged 18 and over.
Four Spanish cities (Barcelona, Castellón, Santiago and Valencia) participate in the Europe-wide annual wastewater campaigns undertaken by the Sewage Analysis Core Group Europe (SCORE). This study provides data on drug use at a municipal level, based on the levels of illicit drugs and their metabolites found in wastewater. The results of the 2017 study on stimulant drugs revealed high levels of cocaine metabolites in wastewater samples from all cities studied, higher than the levels reported in some other European cities participating in the study. In addition, Barcelona recorded an increase in MDMA/ecstasy, amphetamine and methamphetamine residues between 2011 and 2017. A common pattern across the monitored cities was increased use of cocaine and MDMA at weekends.
Data on drug use among 14- to 18-year-old students come from the Spanish Survey on Drug Use in Secondary Schools (ESTUDES), which has been conducted every second year in Spain since 1994. The 2016 study confirmed that the most commonly used illicit substance is cannabis, with about 3 out of 10 students admitting to having used it in the past. No changes were observed in the proportion of students who had used cannabis in the preceding 30 days (18.3 % in 2016; 18.6 % in 2014; 16.1 % in 2012). Lifetime prevalence rates for use of other illicit drugs among students remain well below that for use of cannabis. ESTUDES also supplies data to the European School Project on Alcohol and Drugs (ESPAD), and the 2016 data indicated that prevalence of lifetime cannabis use among Spanish students aged 15-16 years was higher than the ESPAD average (35 countries).
Studies reporting estimates of high-risk drug use can help to identify the extent of the more entrenched drug use problems, while data on first-time entrants to specialised drug treatment centres, when considered alongside other indicators, can inform an understanding of the nature of and trends in high-risk drug use.
In Spain, heroin remains the main substance linked to the most serious adverse health and social consequences, such as drug-related infections. The estimated number of high-risk heroin users has shown a decreasing trend between 2010 and the latest estimate in 2015. The number of high-risk cocaine users in Spain has been falling since 2009. Injecting drug use has also declined in the last 30 years among those admitted to treatment.
Data from specialised treatment centres indicate that cocaine remains the substance resulting in the highest number of treatment entries, while the number of first-time clients reporting cocaine as the primary substance of use has decreased. Only a small proportion of cocaine users entering treatment reported injecting drug use. Further data from treatment centres indicate that cannabis has progressively become the main primary substance among those who enter treatment for the first time. This corresponds to the findings of the last general population study, while the 2014 ESTUDES indicated a slight decline in daily cannabis use among students.