Overall drug use in the United Kingdom has declined from the level seen 10 years ago, remaining stable in the past three years. Because of its relatively high prevalence, cannabis has been a substantial driver of this overall trend. Cannabis remains the most commonly used illicit drug, while powder cocaine is the most prevalent stimulant in the United Kingdom and the second most prevalent drug overall. MDMA/ecstasy is the next most commonly reported stimulant. In general, MDMA users are younger than cocaine and amphetamines users.
According to the Crime Survey for England and Wales, among 16- to 34-year-old young adults, cannabis use declined between 2006 and 2013, but has since levelled off. Cocaine use decreased between 2008 and 2010 and has been relatively stable since. Having previously declined, the level of reported MDMA use has returned to a level broadly similar to that seen around 10 years ago.
Prevalence of new psychoactive substances (NPS) in general population surveys is low in comparison with the main traditional drugs. Mephedrone is the only stimulant NPS to have become established alongside traditional substances among recreational drug users within the general population. However, the prevalence of use of this drug has fallen since the 2010/11 Crime Survey for England and Wales, in which questions were first asked about its use.
Cannabis is the most prevalent drug reported by school surveys and has shown a long-term downward trend with a more recent levelling off that is similar to the trend for the general population. The patterns in school surveys are not unique to cannabis, and are seen in other illicit drug use, as well as in 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 2017, 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 weekends.
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 it appears that there has been a decline in the rate of injecting among opioid users, around one quarter of people who seek treatment for heroin use report its 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 and amphetamines, and the emergence in recent years of the injection of NPS. Studies among vulnerable populations such as homeless people also indicate that the use of synthetic cannabinoid receptor agonists is high among this group.
Data on the characteristics of those entering treatment in the United Kingdom also 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.