Prevalence and trends
Overall prevalence of drug use reported in general population surveys in England and Wales is similar to a decade ago, with almost 1 out of 10 adults aged 16-59 years reporting illicit drug use in the last year. In Scotland, there was a decline in last year illicit drug use between 2008/09 and 2014/15.
In the early 2000s, prevalence of last year cannabis use reported by the Crime Survey for England and Wales was among the highest reported by European countries; however, this is now at a level that is fairly typical to that seen elsewhere in Europe. Following a decrease in prevalence between 2003/04 and 2009/10, the trend in cannabis use in the general population has since been relatively stable. The prevalence rate in 2017/18 was the highest reported since 2008/09; however, the increase from 2016/17 was not statistically significant.
Prevalence of new psychoactive substances (NPS) use in general population surveys is generally low in comparison with the main traditional drugs. Mephedrone was the only stimulant NPS to show signs of becoming established alongside traditional substances among recreational drug users in these surveys. However, prevalence of use of this drug has fallen since the 2010/11 Crime Survey for England and Wales, when questions were first asked about its use.
There was a steady decline in lifetime prevalence of drug use among school children (11- to 15-year-olds) in England between 2004 and 2014; however, an increase was reported in 2016. Drug use prevalence among young people in Scotland has declined since 2004 but remained stable between 2013 and 2015. Cannabis is the most commonly used drug among school children, and there has been a long-term downward trend in reported use with a more recent levelling off that is similar to the trend for the general population. A similar trend is also seen for other illicit drug use, as well as for alcohol and tobacco use.
London and Bristol 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 sources of wastewater. For 2018, only data for Bristol were available. The results pointed to a possible increase in cocaine use in Bristol since the initiation of the study (2014). Furthermore, higher levels of cocaine metabolites were detected at the weekends.
High-risk drug use and trends
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.
Opioids, particularly heroin, remain associated with the greatest health and social harms caused by illicit drugs in the United Kingdom. While there has been a decline in the prevalence of injecting among opioid users, around one third of people who seek treatment for heroin use in England report use by injection. There are concerns about changes in the patterns of drug injection in the United Kingdom, in particular the increased injection of crack cocaine and amphetamine-type stimulants, and the emergence in recent years of the injection of NPS. Data from the 2017 Unlinked Anonymous Monitoring survey of people who inject drugs indicate that the injection of crack has increased in recent years in England and Wales, with 51 % of those who had injected during the preceding 4 weeks reporting the injection of crack cocaine.
Data on the characteristics of those entering treatment in the United Kingdom indicate that heroin is the most commonly reported primary substance among those seeking treatment for drug use problems; however, there has been a long-term reduction in first-time clients seeking treatment for heroin use. Among first-time treatment clients, cannabis is the most commonly reported substance, followed by cocaine. An increase in the number and proportion of first-time treatment entrants for cocaine (both powder and crack) has been reported since 2014. Presentations to community treatment services for primary use of NPS have decreased markedly in England, and problematic NPS use is now found primarily among the adult prison population and street homeless people. Studies among vulnerable populations, such as homeless people, suggest that the use of synthetic cannabinoid receptor agonists is high among this group.