"Illicit drug use disorder is defined as meeting DSM-IV criteria for either dependence or abuse for one or more of the following illicit drugs: marijuana, cocaine, heroin, hallucinogens, inhalants, methamphetamine, or prescription psychotherapeutic drugs that were misused (i.e., pain relievers, tranquilizers, stimulants, and sedatives). There are seven possible dependence criteria for specific illicit drugs:
"1. spent a lot of time engaging in activities related to use of the drug,
"2. used the drug in greater quantities or for a longer time than intended,

"Illicit drug use disorder is defined as meeting DSM-IV criteria for either dependence or abuse for one or more of the following illicit drugs: marijuana, cocaine, heroin, hallucinogens, inhalants, methamphetamine, or prescription psychotherapeutic drugs that were misused (i.e., pain relievers, tranquilizers, stimulants, and sedatives). There are seven possible dependence criteria for specific illicit drugs:

"According to multiple sources, drug users in Russia have numbered between 7.3 to 8.5 million for the past several years. At an October 2017 Saint Petersburg conference, experts reported that in 2016, there were 637,482 people incarcerated in Russia, for which 63 percent were for drug offenses, and 10 percent of whom are HIV positive.

Prevalence of Marijuana Use in Lifetime, Past Year, and Past Month among Persons in the US Aged 12 or Older, by Demographic Characteristics: Number in Thousands

"The UNODC/WHO/UNAIDS/World Bank joint estimate of the number of PWID in 2016 is 10.6 million (range: 8.3 million to 14.7 million), corresponding to 0.22 per cent (range: 0.17 to 0.30 per cent) of the global population aged 15–64 years. This estimate is based on the most recent and highest quality information currently available to UNODC. It does not imply that there has been a change in the global number of PWID compared with those published in previous editions of the World Drug Report.

Click here for complete datatable of Estimated Prevalence of Illegal Substance Use by People Aged 15-64 in Several EU Nations

"As in recent years, the second most commonly used drug in the last year among adults aged 16 to 59 was powder cocaine (2.3% in the 2016/17 survey, equating to around 760,000 people). Powder cocaine was also the second most commonly used drug among young adults aged 16 to 24 (4.8% or around 297,000 young adults) after cannabis. Both proportions remained similar to the previous year (2.2% of 16 to 59 year olds and 4.4% of 16 to 24 year olds in the 2015/16 survey). This trend is illustrated in Figure 1.3.

"As in previous years, cannabis was the most commonly used drug in 2016/17, with 6.6 per cent of adults aged 16 to 59 having used it in the last year (around 2.2 million people), similar to the 2015/16 survey (6.5%). However, this is statistically significantly lower than a decade ago (8.2% in 2006/07) and the start of measurement in the survey in 1996 (9.4%). The trend from the 2009/10 survey onwards is relatively flat, remaining between six and seven per cent, as illustrated by Figure 1.2 (see Appendix Table 1.02 for detailed figures).

"Overall, the number of PWID per 10,000 persons aged 15–64 years varied from 31 to 345 across MSAs [Metropolitan Statistical Areas], median 104.4 (mean 127.4; standard deviation 66.7; percentile range 76–162) in 1992 and from 34 to 324 across MSAs, median 91.5 (mean 103.6; standard deviation 56.4; percentile range 61–125 ) in 2007 indicating an overall decline in PWID prevalence across MSAs.

Illegal Drug Use and Marijuana Use in Lifetime, Past Year, and Past Month among Persons Aged 12 and Older in the US by Age, Gender, and Race/Ethnicity, 2015 and 2016