This website places cookies on your device to help us improve our service to you. To find out more, see our Privacy and Cookies statement.

Drug misuse: availability and prevalence

Because the drug using population is hidden, prevalence figures can only ever be estimates. The prevalence of drug misuse can be derived from numerous sources, for example from surveys (among the general adult population, among school children, among prisoners), from drug offences and drug seizures recorded by the police, from drug testing in prisons, from drug users coming into contact with health care providers because of their drug use or coming forward for treatment.

Assessing the scale of the drug market in Scotland is even more difficult given its illicit nature, although a study published in 2009 (Assessing the Scale and Impact of Illicit Drug Markets in Scotland) provides initial estimates of the size and value of the illicit drugs market and estimates of the social and economic cost of illicit drug use in Scotland for the year 2006. The total value of the illicit drugs market was estimated at around £1.4bn. Heroin held the largest share of the market with 39% of the market, with cannabis holding a 19% share, the second largest. Problem drug users held the largest percentage share of the total market (63%).

Drug seizures by Scottish police forces

The publication Drug Seizures and Offender Characteristics, 2014/15 and 2015/16 (Tables) presents data on the number of drug seizures made by the police in Scotland and the characteristics of individuals found in possession of drugs in 2014/15 and 2015/16. These statistics relate to substances controlled under the Misuse of Drugs Act 1971, which divides drugs into three classes (A, B and C).

Changes to the data collection process means that the 2014/15 and 2015/16 figures are not directly comparable with the figures produced for previous years. For the first time, information on seizures related to drug supply crimes is supplemented by data from an annual random sample of 400 individuals found in possession of drugs. Information from this sample is used to estimate the number of seizures and quantities of drugs seized as a result of drug possession offences and as the basis for analysis of offender characteristics.

Key points:

  • For crimes of drug supply, drug production or illegal importation of drugs, the main Class A drugs seized by Police Scotland in 2015/16 were cocaine powder (82.7 kilograms), heroin (74.0 kilograms) and crack cocaine (4.2 kilograms). In addition to this, approximately 13,400 ecstasy-type tablets were seized (Table 1).
  • For crimes of drug supply, drug production or illegal importation of drugs, the main Class B drugs seized by Police Scotland in 2015/16 were cannabis resin (570.4 kilograms) and herbal cannabis (413.9 kilograms). Approximately 31,400 cannabis plants were also seized (Table 2).
  • For crimes of drug supply, drug production or illegal importation of drugs, the main Class C substances seized in 2015/16 were ‘diazepam or other benzodiazepines’ (excluding temazepam) (approximately 1.28 million tablets) (Table 3).
  • Where it was possible to include information from drug supply and drug possession offences, the total amount of drugs seized in 2015/16 was:
    • Cocaine (class A): 88.8 kilograms
    • Heroin (class A): 76.1 kilograms
    • Cannabis Resin (class B): 588.0 kilograms
    • Herbal Cannabis (class B): 450.7 kilograms
    • Diazepam (class C): 1.34 million tablets (Table 7)
  • A sample of drug possession crimes found that 64% of such crimes in 2015/16 involved seizure of herbal cannabis or cannabis resin, while 12% involved seizure of diazepam (Table 6).
  • The vast majority of drug possession offences (around 87%) involved males. The mean average age of an offender was 30 years old, with the majority (65%) being between 20 and 39 years old. 16% of offenders were under 20 years old and 19% were 40 years old or older (Table 8).

Drug Misuse and Treatment in Scottish Prisons

Addiction Prevalence Testing (APT) is conducted across all Scottish prisons annually. During one month of the year, prisoners arriving in custody are tested for the presence of illegal drugs. Similarly, those leaving custody during the month are tested to assess progress towards the 'reduced or stabilised' offender outcome. Results from these tests can be found in the table SPS Addiction Prevalence Testing Stats Final 2016/17 (30Kb).

Key points:

  • Of the 1,026 tests carried out when entering prison (reception) in 2016/17, 79% were positive for drugs (including drugs prescribed as part of a treatment programme) and 76% were positive for illegal drugs (including illicit use of prescribed drugs). Since 2010/11, the percentage testing positive for illegal drugs when entering prison has been relatively stable, ranging between 70% and 77%.
  • The drugs most commonly detected when entering prison in 2016/17 were cannabis (47% of tests (52% in 2015/16)), benzodiazepines (41% of tests (35% in 2015/16)) and opiates (codeine, morphine, dihydrocodeine or heroin) (33% of tests (25% in 2015/16)). Cocaine presence increased from 15% of tests in 2015/16 to 20% in 2016/17. Selected opioids (buprenorphine, methadone and tramadol) were subject to specific tests – of these, the most commonly detected was buprenorphine (10% of tests (7% in 2015/16)).
  • Of the 633 tests carried out when leaving prison (liberation) in 2016/17, 30% were positive for illegal drugs. The percentage of individuals who tested positive for illegal drugs when leaving prison has gradually increased since 2009/10 (17%).
  • The drugs most commonly detected when leaving prison in 2016/17 were buprenorphine (12% of tests in 2016/17 and 2015/16), cannabis (9% of tests in 2016/17 (8% in 2015/16)) and opiates (9% of tests in 2016/17 (8% in 2015/16)). In 2016/17, buprenorphine was the only substance more prevalent in liberation tests (12%) than in reception tests (10%).

Previous year's APT findings can be found here:

The Scottish Prisoners Survey 2015 was undertaken in each of the 15 Scottish prisons and involved all prisoners. The main survey achieved a response rate of 55%. 92% of respondents were male and the average age of respondents was 33 years. Four in five respondents (80%) were convicted; the remainder were untried.

Key points:

  • The percentage of prisoners who stated that they were under the influence of drugs at the time of their offence was 40% in 2015 (similar to 2013: 39%). Around one-sixth of prisoners (17%) reported that they committed their offence to get money for drugs (similar to 2013: 16%).
  • The percentage of prisoners who stated their drug use was a problem for them outside prison increased from 35% in 2013 to 38% in 2015. Around one fifth (21%) were receiving treatment for drug use before they were imprisoned (the same as in 2013: 21%).
  • In 2015, 43% reported that they had used illegal drugs while in prison; an increase from 38% in 2013, but lower than the percentages recorded in previous surveys (2001: 58%, 2008: 48%, 2011: 45%). Of these prisoners, three in four (76%) stated that their drug use had changed during their current period of imprisonment. Most of those reporting change (60%) stated their drug use had decreased, 20% reported it had increased, 10% reported their drug use had remained the same but they used different drugs and 10% stated that they had started using drugs whilst in prison (Main Bulletin – Figure 1).
  • One quarter of prisoners (24%) reported using drugs in the previous month while in prison (2011: 20%, 2013: 28%). In 2015, cannabis (61%), buprenorphine/subutex (39%), benzodiazepines (39%) and heroin (33%) were the most commonly reported drugs (Main Bulletin - Figure 2). The percentage of recent users taking heroin in the past month decreased from 71% in 2011 to 37% in 2013 and 33% in 2015.
  • Overall, 27% reported using novel‘ or ‘new’ psychoactive substances (NPS)/legal highs at any point prior to imprisonment (an increase from 23% in 2013).  Of these, 60% had used synthetic cannabinoids, 60% used stimulants, 31% used a hallucinogen, 16% used a ‘downer’ and (4%) reported being unsure what they were using (Main Bulletin - Figure 3).
  • Around one-tenth of prisoners (11%) reported using NPS/legal highs in prison (an increase from 8% in 2013).  Of these, four-fifths (82%) reported using synthetic cannabinoids, 42%, used stimulants, 31% used hallucinogens, 15% reported that they had used a ‘downer’ and 15% were unsure what they had used (Main Bulletin - Figure 4).
  • A small minority of prisoners reported injecting drugs in prison ever (6%) or in the past month (2%); these percentages were the same as in 2013. Among injectors, 82% (n=48) reported sharing injecting equipment. Heroin was the most commonly injected drug among this group.
  • Two in five prisoners (39%) reported being assessed for drug use when admitted to prison. This was a decrease from 56% in 2011 and 46% in 2013. There was also a decrease in prisoners being given the chance to receive treatment for drug use (2011: 41%, 2013: 33% 2015: 28%) and in receiving treatment for drug use during their sentence (2011: 36%, 2013: 28%, 2015: 24%) (Main Bulletin – Table 6).
  • Two-fifths of prisoners (42%) stated they would accept help for a drug problem in prison or stated they would accept help on the outside (39%). Only one quarter of prisoners (24%) thought that their drug use would be a problem for them when they were released from prison (Main Bulletin – Table 6).
  • Overall, one-fifth of prisoners (20%) reported being prescribed methadone in prison (roughly the same as in 2013: 21%). Of these, over half were on a maintenance dose (57%), around one-fifth (22%) were on a stabilising dose and one further fifth on a reducing dose (21%). Of those currently prescribed methadone, 26% stated that they had taken another prisoner’s prescribed medication while in prison.
  • 13% of prisoners (488) reported having been supplied with naloxone. Of those, 52% (255) had been supplied with naloxone in the last 12 months. Where a prisoner had received naloxone in the previous 12 months, over half (141, 55%) received it in prison and over two-thirds (173, 68%) had received it in the community. Around one in 20 prisoners (246, 6%) had given naloxone to someone else and of those, 50% (124) had done so in the previous 12 months (Main Bulletin – Table 5).

Illicit drug use among adults

Information on the extent of illicit drug use is derived from surveys of samples of the general population. Collecting accurate information on illicit drug use is notoriously difficult because of its hidden and illegal nature. Surveys vary in terms of the number of participants and the degree to which they are representative of the wider population and, therefore, some caution is needed in interpretation of estimates.

The Scottish Crime and Justice Survey is one source of information on illicit drug use among adults.

Key points:

  • In 2014/15, six per cent of respondents (aged 16 years and over) had used illicit drugs during the previous year, compared with 6.6% in 2010/11 and 6.2% in 2012/13 (P34).
  • Higher levels of drug misuse were reported among males than females. In 2014/15, 8.9% of males aged 16 and over reported illicit drug use in the previous year, compared to 3.4% of females.
  • Individuals aged 16-24 were most likely to report using drugs in the last year (18.8%), compared with 8.3% of those aged 25-44, 2.7% of 45-59-year-olds and 0.2% of those aged 60 or older (P34).
  • In 2014/15, the most commonly reported illicit drug used within the last year was cannabis (5.0% of adults), followed by cocaine (1.8%) and ecstasy (1.3%).
  • Among adults who had used illicit drugs in the last month, most said that it was very easy (40.5%) or fairly easy (43.4%) to get hold of the drug they used most often (P87).
  • Among adults who had used more than one illicit drug in the last year, half (50.6%) had taken more than one drug at the same time (P54).
  • Among adults who had used illicit drugs at some point in their lives, 77.8% reported that their first drug used was cannabis (P13).

Illicit drug use among children

A key source of information on illicit drug use among children and young people is the Scottish Schools Adolescent Lifestyle and Substance Use Survey (SALSUS). Some key points from the 2015 survey are summarised below:

  • 19% of 15-year-olds and five per cent of 13-year-olds reported ever taking drugs, compared to 11% of 15-year-olds and three per cent of 13-year-olds who reported taking drugs in the last month.
  • The most commonly reported illicit drug used was cannabis. In the 2015 survey, 10% of 15 year olds reported using cannabis in the last month and 17% reported ever using cannabis.  Smaller percentages of 15-year-olds reported ever using other drugs, e.g. ecstasy (5%), cocaine (4%), and NPS (5%). Due to small numbers, no data were available for 13-year-olds.
  • Prevalence of reported drug use in the last month among 13 and 15-year-old boys and girls has declined markedly since 1998. The percentage of 15-year-olds who reported using drugs in the month before the survey fell from 24% in 1998 to 11% in 2015. Similarly, the percentage of 13-year-olds who reported using drugs in the month prior to the survey decreased from 8% in 1998 to 3% in 2015. However, this figure has risen slightly since 2013 (9% of 15-year-olds; 2% of 13-year-olds).
  • Between 1998 and 2015, the proportion of 15-year-olds who never used drugs increased from 61% in 1998 to 81% in 2015 and for 13-year-olds from 87% in 1998 to 95% in 2015. This was a slight decrease from 2013 (82% of 15-year-olds; 96% of 13-year-olds).

Estimated prevalence of problem drug use

The group of drug users who are most likely to experience health and social problems are those who misuse opiates (primarily heroin) and/or benzodiazepines (tranquillisers). It is this group who are also most vulnerable to acquiring communicable diseases (such as HIV and hepatitis primarily through sharing injecting equipment) are involved in a high number of crimes/offences and, subsequently, have a high risk of imprisonment.

In 2014, ISD Scotland published a report providing estimates of the national and local prevalence of problem drug use in Scotland in 2012/13 .

Key points:

  • The estimated number of individuals with problem drug use in Scotland during 2012/13, aged 15-64 years old, was 61,500 (95% CI = 59,900 - 63,300). The equivalent estimate for 2009/10, was 59,600 (95% CI = 58,300 - 61,000).
  • Expressed as a percentage of the population, the rate of problem drug use in 2012/13 was 1.74% (95% CI = 1.69% – 1.79%). This compares to an estimate of 1.71% (95% CI 1.67% - 1.75%) in 2009/10.
  • As in previous years, the majority of individuals with problem drug use in Scotland during 2012/13 were male (70%). The estimated prevalence rate of problem drug use was 2.49% of all males aged 15-64 years, and 1.01% of all females aged 15-64 years, resident in Scotland during 2012/13.
  • The proportion of all male problem drug users that are aged 35-64 has increased from 43% in 2009/10 to 51% in 2012/13.
  • Prevalence rates of problem drug use tended to be higher in non-rural areas; the four major cities of Aberdeen, Dundee, Edinburgh and Glasgow were all above the Scottish cumulative rate. Similarly, Inverclyde, North Ayrshire, Renfrewshire and West Dunbartonshire were also higher than the Scottish rate. According to the Scottish index of multiple deprivation 2012, these council areas serve some of the most deprived communities in Scotland.
  • The alcohol and drug partnerships (ADPs) with the highest prevalence rates of problem drug use were Glasgow City (3.2%, 95%CI=3.1%-3.4%), Inverclyde (3.2%, 95%CI= 2.9%-3.6%) and Dundee City (2.8%, 95%CI = 2.5-3.1).
  • The lowest estimates were observed in Orkney (0.2%, 95%CI=0.1%-0.8%), East Dunbartonshire (0.6%, 95%CI=0.4%-0.8%) and Moray(0.6%, 95%CI=0.4%-0.8%).

Although injecting prevalence was not reported in the 2014 publication, an estimate was provided in a previous prevalence report based on 2006 data (Hay et al, 2009).

  • In 2006, there were an estimated 23,933 people injecting opiates and/or benzodiazepines. The highest drug injecting prevalence rates by council area were identified in Inverclyde at 1.63% (95% CI 1.30-2.07%) of the population aged 15-64, followed by Aberdeen City and Glasgow City with prevalence rates of 1.56% (95% CI 1.25-1.98%) and 1.35% (95 CI 1.08-1.72%) respectively.
  • The estimated prevalence of problem drug use in Scotland among 15-64-year-olds is also included in the ScotPHO Drugs Profile (for males, females and both genders), so can be explored by NHS Board and ADP area.

Please note: If you require the most up-to-date data available, please check the data sources directly as new data may have been published since these data pages were last updated. Although we endeavour to ensure that the data pages are kept up-to-date, there may be a time lag between new data being published and the relevant ScotPHO web pages being updated.

Page last updated: 15 September 2017

© Scottish Public Health Observatory 2014