The most recent general population survey shows that cannabis remains the most frequently used illicit substance in Portugal, followed by MDMA/ecstasy and cocaine. Use of illicit substances is more common among young adults (aged 15-34 years). The available data indicate an increase in last year and last month cannabis use during the period 2012-16, mainly among those aged between 25 and 44 years.
In 2017, the third edition of the Survey on Addictive Behaviours among people aged 18 years took place; young people participating in the National Defence Day were surveyed. Cannabis was the substance with the highest prevalence of use. A slight decrease in the prevalence of cocaine use relative to previous years was observed.
Lisbon, Almada and Porto participate in the Europe-wide annual wastewater campaigns undertaken by the Sewage Analysis Core Group Europe (SCORE); 2018 data are not available for Porto, however. 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 indicate an increase in cocaine and MDMA use in Lisbon between 2013 and 2018, and the use of these substances seems to be more common in Lisbon than in Porto or Almada (in 2016 and 2017). Moreover, in all locations the presence of these substances in wastewater was higher at weekends than on weekdays. In 2018, amphetamine and methamphetamine levels detected in the two cities remained low, indicating very limited use of these substances in these cities.
The most recent data on drug use among students were reported in the 2015 European School Survey Project on Alcohol and Other Drugs (ESPAD). Lifetime use of cannabis and other illicit substances among Portuguese students was slightly lower than the European average (based on data from 35 countries), with lifetime use of new psychoactive substances much lower than the average. Similarly, use of cigarettes in the last 30 days was just below the European average and alcohol use and binge drinking in the last 30 days were much lower than the average. Lifetime use of cannabis showed an increase in the 2003 survey, but it has remained relatively stable since, as indicated in the three subsequent surveys.
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.
It is estimated that there were 33 290 high-risk opioid users in Portugal in 2015, which is about 5.2 per 1 000 of the adult population. In the same year, the number of people who inject drugs was estimated at 13 160 (2 per 1 000 people aged 15-64).
The Cannabis Abuse Screening Test included in the 2016/17 general population survey suggested that about 0.7 % of 15- to 64-year-olds could be considered high-risk cannabis users.
Data from specialised treatment centres show that the first-time treatment demands attributable to heroin use have declined since 2009. In contrast, first-time treatment entries resulting from the primary use of cannabis increased until 2016 and have since stabilised. Following a period of stability in cocaine-related first-time treatment demands, an increase has been noted in the past few years. In general, males accounted for the majority of treatment entrants.