Prevalence of Illegal Drug Use in Australia: "There was no change in recent use of most illicit drugs in 2013, and use of any illicit drug remained stable between 2010 and 2013. However, there was a significant change for a few specific drugs. The proportion of people who had misused a pharmaceutical rose from 4.2% in 2010 to 4.7% in 2013, whereas there were falls in the use of ecstasy (from 3.0% to 2.5%), heroin (from 0.2% to 0.1%) and gamma hydroxybutyrate (GHB).
"NSDUH’s overall estimates of SUD [Substance Use Disorder] include people who met the DSM-IV criteria for either dependence or abuse for alcohol or illicit drugs. In 2018, approximately 20.3 million people aged 12 or older had an SUD in the past year, including 14.8 million who had an alcohol use disorder and 8.1 million who had an illicit drug use disorder (Figure 42). Among the 8.1 million people who had an illicit drug use disorder, the most common disorders were for marijuana (4.4 million) and misuse of prescription pain relievers (1.7 million).
"It is estimated that in 2016 some 275 million people worldwide had used drugs at least once in the previous year (range: 204 million to 346 million). Corresponding to 5.6 per cent of the global population aged 15–64 years (range: 4.2 to 7.1 per cent), or approximately 1 of every 18 people. The actual number of people who use drugs increased by 20 million people from 2015 to 2016.