Trends in drugs of concern
People enter alcohol and other drug (AOD) treatment to identify and assess harmful use of one or more substances. The principal drug of concern (PDOC) is the main substance that led the person to seek support. AOD services can facilitate referral into intensive interventions if required, also providing coordinated care and case management services, with an aim to match the person’s needs and the interventions being offered.
This section presents information on treatment episodes provided to clients for their own AOD use only. The principal drug of concern (PDOC) is the main substance that the client stated led them to receive treatment. It is assumed that only the person using a substance themselves can accurately report their principal drug of concern. Clients can also nominate up to 5 additional drugs of concern, though these are not necessarily the subject of any treatment within the episode.
These data are not collected for people who received treatment for someone else’s drug use.
This section focuses on treatment episodes provided for alcohol, methamphetamine, cannabis and heroin as the PDOC. These 4 drugs were consistently the most common principal drugs of concern across Australia in the 10-year period up to 2024–25. For detailed information on each drug of concern, refer to the technical notes.
Treatment episodes and drugs of concern
In 2024–25, 214,662 (88%) treatment episodes were provided to 117,132 clients for their own AOD use (Table OV.1).
Of these episodes:
- The most common principal drugs of concern were alcohol (41% of episodes), followed by methamphetamine (24%), cannabis (14%) and heroin (4.3%) (Table Drg.1).
- 30% of treatment episodes reported at least 1 additional drug of concern. The most common additional drugs of concern were cannabis (12%), followed by nicotine (10%) and alcohol (7.1%) (tables Drg.1, Drg.2, Drg.3).
- The number of additional drugs reported was most commonly one drug (19%) or 2 drugs (7.2%).
- For the 4 most common principal drugs of concern, the most common treatment setting was non-residential treatment settings ranging from:
- 75% of episodes for heroin.
- 69% of episodes for alcohol.
- 67% of episodes for cannabis.
- 65% of episodes for methamphetamine (Table Drg.8).
Between 2015–16 to 2024–25, of the clients who received treatment for their own AOD use:
- Client numbers decreased by 9.1%, from a peak in 2019–20 (128,860) to 117,132 in 2024–25.
- The number of treatment episodes also decreased by 4.2%, from a peak in 2020–21 (224,135) to 214,662 in 2024–25 (Table OV.1).
- The drop in the number of clients receiving AOD treatment may also be due to changes in funding for services, agencies reporting for only part of the financial year, and system issues resulting in problems collecting or extracting AODTS NMDS data.
- There were fewer clients receiving treatment for their own AOD use, but on average clients received more than one treatment episode within a year. Indicating that although fewer people are accessing services, those who do receive treatment are receiving multiple episodes of care (Table SCR.27).
Between 2015–16 to 2024–25, for the 4 most common principal drugs of concern:
- Alcohol remained the most common principal drug of concern each year.
- Alcohol treatment episodes showed some variation in treatment activity over this period, with the number of episodes falling since 2022–23 (from 92,417 to 87,632).
- Methamphetamine episodes as a principal drug of concern rose from 22% in 2019–20 (47,599) to 24% (50,863) in 2024–25. In 2019–20 improvements in data reliability for methamphetamine treatment episodes led to greater consistency in reporting.
- Treatment episodes for cannabis as the principal drug of concern fell from 23% to 14% (45,043 to 30,287).
- The number of treatment episodes for heroin as the principal drug of concern peaked in 2019–20 (11,133 or 5.1%) falling to 9,204 (4.3%) in 2024–25 (Table Drg.5).
Changes in certain principal drug treatment episodes in particular years may be due to administrative anomalies in the data. For example, the drop in all treatment episodes in the 2016–17 collection year may be partly related to state and territory policy changes, state system changes resulting in under-reporting or partial reporting of the number of episodes in some jurisdictions (See the Data quality statement for further details).