Health :: The National Alcohol and Drug Knowledgebase

Are Australians who use pharmaceutical drugs for non-medical purposes more likely to be diagnosed with/treated for mental illnesses, compared to those who use pharmaceutical drugs for medical purposes only?

In general, a larger proportion of Australians who have used pharmaceutical drugs^†for non-medical purposes in their lifetime have been diagnosed with/treated for a mental illness, compared to those who have used pharmaceutical drugs for medical purposes only.

Source: Australian Institute of Health and Welfare (AIHW). 2019 National Drug Strategy Household Survey (NCETA secondary analysis, 2021).

† This FAQ uses data from the National Drug Strategy Household Survey, which defines the pharmaceutical drugs referred to in this question as: the medical or non-medical use of pain-killers/pain-relievers/opioids (oxycodone, morphine, codeine products such as panadeine forte (excluding paracetamol, asprin and ibuprofen where these drugs are the only active ingredients)), tranquillisers/sleeping pills (e.g., sleepers, benzos, tranks, temazzies, temaze, rivotril, serepax, serries, xanax, xannies, stilnox, rohypnol, rowies, valium) and methadone/buprenorphine (e.g., done, junk, jungle juice, bupe, sub).

Please note: The proportion of individuals who use pharmaceutical drugs for non-medical purposes and have been diagnosed with a mental illness reported here may differ from other FAQs, due to response rate variations in the source data.

Non-medical use: A drug used:

By itself to induce a drug experience or feeling; or
With other drugs in order to enhance a drug experience.

* Estimate has a relative standard error of 25% to 50% and should be used with caution.

How many Australians are hospitalised each year due to pharmaceutical drug use?

There were 7,707 hospital separations due to pharmaceutical drug use in 2022-23.

Source: Australian Institute of Health and Welfare (AIHW). National Hospital Morbidity Database, 2022-23 (NCETA secondary analysis, 2024).

Please note: This FAQ uses data from the National Hospital Morbidity Database, which includes the following causes of hospitalisation considered to be related to the use of pharmaceutical drugs: Poisoning by salicylates; Poisoning by other nonopioid analgesics and antipyretics, not elsewhere classified; Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified; Poisoning by other opioids; Poisoning by methadone; Poisoning by other synthetic narcotics; Poisoning by benzodiazepines; Mental and behavioural disorders due to use of sedatives or hypnotics; Opioids and related analgesics causing adverse effects in therapeutic use; Salicylates causing adverse effects in therapeutic use; and Benzodiazepines causing adverse effects in therapeutic use. However, in 2020-21 data were not available for: Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified; Opioids and related analgesics causing adverse effects in therapeutic use; Salicylates causing adverse effects in therapeutic use; and Benzodiazepines causing adverse effects in therapeutic use.

The National Hospital Morbidity Database cannot distinguish between hospital separations due to non-medical use of pharmaceuticals and hospital separations due to the use of pharmaceuticals as directed by a doctor.

Hospital Separation: An episode of care for an admitted patient, which can be:

a total hospital stay (from admission to discharge, transfer or death); or
a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute to rehabilitation).

Separation also means the process by which an admitted patient completes an episode of care either by being discharged, transferring to another hospital, changing type of care, or dying.

Are men or women in Australia more likely to be hospitalised due to pharmaceutical drug use?

In 2022-23, women accounted for more hospital separations due to pharmaceutical drug use than men (60% vs 36%, respectively).

Source: Australian Institute of Health and Welfare (AIHW). National Hospital Morbidity Database, 2020-21 (NCETA secondary analysis, 2022).

Please note: This FAQ uses data from the National Hospital Morbidity Database, which includes the following causes of hospitalisation considered to be related to the use of pharmaceutical drugs: Poisoning by salicylates; Poisoning by other nonopioid analgesics and antipyretics, not elsewhere classified; Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified; Poisoning by other opioids; Poisoning by methadone; Poisoning by other synthetic narcotics; Poisoning by benzodiazepines; Mental and behavioural disorders due to use of sedatives or hypnotics; Opioids and related analgesics causing adverse effects in therapeutic use; Salicylates causing adverse effects in therapeutic use; and Benzodiazepines causing adverse effects in therapeutic use. However, in 2020-21 data were not available for: Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified; Opioids and related analgesics causing adverse effects in therapeutic use; Salicylates causing adverse effects in therapeutic use; and Benzodiazepines causing adverse effects in therapeutic use.

The National Hospital Morbidity Database cannot distinguish between hospital separations due to non-medical use of pharmaceuticals and hospital separations due to the use of pharmaceuticals as directed by a doctor.

Hospital Separation: An episode of care for an admitted patient, which can be:

a total hospital stay (from admission to discharge, transfer or death); or
a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute to rehabilitation).

Separation also means the process by which an admitted patient completes an episode of care either by being discharged, transferring to another hospital, changing type of care, or dying.

Are younger or older Australians more likely to be hospitalised due to pharmaceutical drug use?

In 2022-23, the largest proportion of hospital separations due to pharmaceutical drug use (22%) occurred among 20-29 year olds, followed by 60+ year olds (21%).

Source: Australian Institute of Health and Welfare (2023). National Hospital Morbidity Database, 2022-23 (NCETA secondary analysis, 2024).

Please note: This FAQ uses data from the National Hospital Morbidity Database, which includes the following causes of hospitalisation considered to be related to the use of pharmaceutical drugs: Poisoning by salicylates; Poisoning by other nonopioid analgesics and antipyretics, not elsewhere classified; Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified; Poisoning by other opioids; Poisoning by methadone; Poisoning by other synthetic narcotics; Poisoning by benzodiazepines; Mental and behavioural disorders due to use of sedatives or hypnotics; Opioids and related analgesics causing adverse effects in therapeutic use; Salicylates causing adverse effects in therapeutic use; and Benzodiazepines causing adverse effects in therapeutic use.

However, in 2022-23 data were not available for: Opioids and related analgesics causing adverse effects in therapeutic use; Salicylates causing adverse effects in therapeutic use; and Benzodiazepines causing adverse effects in therapeutic use.

The National Hospital Morbidity Database cannot distinguish between hospital separations due to non-medical use of pharmaceuticals and hospital separations due to the use of pharmaceuticals as directed by a doctor.

Hospital Separation: An episode of care for an admitted patient, which can be:

a total hospital stay (from admission to discharge, transfer or death); or
a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute to rehabilitation).

Separation also means the process by which an admitted patient completes an episode of care either by being discharged, transferring to another hospital, changing type of care, or dying.

What are the most common types of pharmaceutical drug-related harms for which Australians are hospitalised?

Two types of pharmaceutical drug-related harms resulted in hospital separations in 2022-23. These were ‘poisoning by pharmaceutical drugs’ (accounting for 70% of separations) and ‘mental and behavioural disorders due to the use of pharmaceutical drugs’ (accounting for 30% of separations).

Source: Australian Institute of Health and Welfare (2023). National Hospital Morbidity Database, 2022-23 (NCETA secondary analysis, 2024).

Please note: For the purpose of this FAQ, poisoning by pharmaceutical drugs includes: Poisoning by salicylates; Poisoning by other nonopioid analgesics and antipyretics, not elsewhere classified; Poisoning by other opioids; Poisoning by methadone; Poisoning by other synthetic narcotics; and Poisoning by benzodiazepines. Mental and behavioural disorders due to the use of pharmaceutical drugs includes: Mental and behavioural disorders due to use of sedatives or hypnotics. However, in 2022-23 data were not available for: Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified.

The National Hospital Morbidity Database cannot distinguish between hospital separations due to non-medical use of pharmaceuticals and hospital separations due to the use of pharmaceuticals as directed by a doctor.

Hospital Separation: An episode of care for an admitted patient, which can be:

a total hospital stay (from admission to discharge, transfer or death); or
a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute to rehabilitation).

Separation also means the process by which an admitted patient completes an episode of care either by being discharged, transferring to another hospital, changing type of care, or dying.

Are men and women in Australia hospitalised for different types of pharmaceutical drug-related harms?

In 2022-23, Australian men and women were both most likely to be hospitalised for poisoning by pharmaceutical drugs.

Source: Australian Institute of Health and Welfare (2023). National Hospital Morbidity Database, 2022-23 (NCETA secondary analysis, 2024).

Please note: For the purpose of this FAQ, poisoning by pharmaceutical drugs includes: Poisoning by salicylates; Poisoning by other nonopioid analgesics and antipyretics, not elsewhere classified; Poisoning by other opioids; Poisoning by methadone; Poisoning by other synthetic narcotics; and Poisoning by benzodiazepines. Mental and behavioural disorders due to the use of pharmaceutical drugs includes: Mental and behavioural disorders due to use of sedatives or hypnotics. However, in 2020-21 data were not available for: Poisoning by nonopioid analgesic, antipyretic and antirheumatic, unspecified.

The National Hospital Morbidity Database cannot distinguish between hospital separations due to non-medical use of pharmaceuticals and hospital separations due to the use of pharmaceuticals as directed by a doctor.

Hospital Separation: An episode of care for an admitted patient, which can be:

a total hospital stay (from admission to discharge, transfer or death); or
a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute to rehabilitation).

Separation also means the process by which an admitted patient completes an episode of care either by being discharged, transferring to another hospital, changing type of care, or dying.

Are younger and older Australians hospitalised for different types of pharmaceutical drug-related harms?

In 2022-23, poisonings were the most common type of pharmaceutical drug-related harm for which Australians were hospitalised across all age groups. Mental and behavioural disorders were most prevalent among those aged 20-29 and 30-39 years.

Source: Australian Institute of Health and Welfare (2023). National Hospital Morbidity Database, 2022-23 (NCETA secondary analysis, 2024).

Please note: For the purpose of this FAQ, poisoning by pharmaceutical drugs includes: Poisoning by salicylates; Poisoning by other nonopioid analgesics and antipyretics, not elsewhere classified; Poisoning by other opioids; Poisoning by methadone; Poisoning by other synthetic narcotics; and Poisoning by benzodiazepines. Mental and behavioural disorders due to the use of pharmaceutical drugs includes: Mental and behavioural disorders due to use of sedatives or hypnotics.

The National Hospital Morbidity Database cannot distinguish between hospital separations due to non-medical use of pharmaceuticals and hospital separations due to the use of pharmaceuticals as directed by a doctor.

Hospital Separation: An episode of care for an admitted patient, which can be:

a total hospital stay (from admission to discharge, transfer or death); or
a portion of a hospital stay beginning or ending in a change of type of care (for example, from acute to rehabilitation).

Separation also means the process by which an admitted patient completes an episode of care either by being discharged, transferring to another hospital, changing type of care, or dying.

Are Australians who use pharmaceutical drugs for non-medical purposes more likely to have high psychological distress compared to those who use pharmaceutical drugs for medical purposes only?

In general, Australians who have used pharmaceutical drugs^† for non-medical purposes in the their lifetime are more likely to report high or very high levels of psychological distress, compared to those who use pharmaceutical drugs for medical purposes only.

Source: Australian Institute of Health and Welfare (AIHW). 2019 National Drug Strategy Household Survey (NCETA secondary analysis, 2021).

† This FAQ uses data from the National Drug Strategy Household Survey, which defines the pharmaceutical drugs referred to in this question as: the non-medical use of pain-killers/pain-relievers/opioids (oxycodone, morphine, codeine products such as panadeine forte (excluding paracetamol, asprin and ibuprofen where these drugs are the only active ingredients)), tranquillisers/sleeping pills (e.g., sleepers, benzos, tranks, temazzies, temaze, rivotril, serepax, serries, xanax, xannies, stilnox, rohypnol, rowies, valium) and methadone/buprenorphine (e.g., done, junk, jungle juice, bupe, sub).

* Estimate has a relative standard error of 25% to 50% and should be used with caution.

** Estimate has a relative standard error greater than 50% and is considered too unreliable for general use.

Please note: The proportion of individuals who use pharmaceutical drugs for non-medical reasons and are psychologically distressed reported here may differ from other FAQs, due to response rate variations in the source data.

Non-medical use: Drugs used:

By itself to induce a drug experience or feeling; or
With other drugs in order to enhance a drug experience.

What are the diagnostic criteria for pharmaceutical drug-related mental health disorders?

One of the reference guides used by clinicians to diagnose mental health disorders is known as the Diagnostic and Statistical Manual of Mental Disorders (DSM). The most recent version of the manual, the Diagnostic and Statistical Manual of Mental Disorders – 5th Edition (DSM-5), was released in May 2013. Prior to this, the Diagnostic and Statistical Manual of Mental Disorders – 4th Edition, Text Revision (DSM-IV-TR) was used by clinicians and researchers from 2000 to 2013.

The diagnostic criteria for mental health disorders due to pharmaceutical drug use differ significantly between the DSM-IV-TR and the new DSM-5. For the purposes of the NADK, all reported data on pharmaceutical drug-related mental health disorders utilise the DSM-IV-TR diagnostic criteria. This is because the relevant mental health data reported in the NADK were collected prior to the publication of the newer version of the DSM (DSM-5).

DSM-IV-TR Diagnostic Criteria

According to the DSM-IV-TR, there are two main pharmaceutical drug-related mental health disorders: substance dependence and substance abuse. The diagnostic criteria for each are presented below.

Substance Dependence

A maladaptive pattern of substance use, leading to clinically significant impairment or distress, as manifested by three (or more) of the following, occurring at any time in the same 12-month period:

Tolerance, as defined by either of the following:
a. A need for markedly increased amounts of the substance to achieve intoxication or desired effect; or
b. Markedly diminished effect with continued use of the same amount of the substance
Withdrawal, as manifested by either of the following:
a. The characteristic withdrawal syndrome for the substance; or
b. The same (or a closely related) substance is taken to relieve or avoid withdrawal symptoms
The substance is often taken in larger amounts or over a longer period than was intended
There is a persistent desire or unsuccessful efforts to cut down or control substance use
A great deal of time is spent on activities necessary to obtain the substance (e.g., visiting multiple doctors or driving long distances), use the substance, or recover from its effects
Important social, occupational, or recreational activities are given up or reduced because of substance use
The substance use is continued despite knowledge of having a persistent physical or psychological problem that is likely to have been caused or exacerbated by the substance.

Substance Abuse

A maladaptive pattern of substance use leading to clinically significant impairment or distress, as manifested by one (or more) of the following, occurring within a 12-month period:

Recurrent substance use resulting in a failure to fulfil major role obligations at work, school, or home (e.g., repeated absences or poor work performance related to substance use; substance‐related absences, suspensions, or expulsions from school; neglect of children or household)
Recurrent substance use in situations in which it is physically hazardous (e.g., driving an automobile or operating a machine when impaired by substance use)
Recurrent substance‐related legal problems (e.g., arrests for substance‐related disorderly conduct)
Continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance (e.g., arguments with spouse about consequence of intoxication, physical fights).

DSM-5 Diagnostic Criteria

According to the DSM-5, there is one main substance related mental health disorder: A substance use disorder.

A substance use disorder is defined as:

A pattern of substance use leading to clinically significant impairment or distress, as manifested by at least two of the following, occurring within a 12-month period:

The substance is often taken in larger amounts or over a longer period than was intended
There is a persistent desire or unsuccessful efforts to cut down or control substance use
A great deal of time is spent in activities necessary to obtain the substance, use the substance, or recover from its effects
Having craving, or a strong desire or urge to use the substance
Recurrent substance use resulting in a failure to fulfil major role obligations at work, school, or home
Continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance
Important social, occupational, or recreational activities are given up or reduced because of substance use
Recurrent substance use in situations in which it is physically hazardous
Substance use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by the substance
Tolerance, as defined by either of the following:
a. A need for markedly increased amounts of the substance to achieve intoxication or desired effect.
b. A markedly diminished effect with continued use of the same amount of the substance.
Withdrawal, as manifested by either of the following:
a. The characteristic withdrawal syndrome for the substance
b. The substance (or a closely related substance) is taken to relieve or avoid withdrawal symptoms.

A mild substance use disorder is defined as the presence of 2-3 of the above symptoms.

A moderate substance use disorder is defined as the presence of 4-5 of the above symptoms.

A severe substance use disorder is defined as the presence of 6 or more of the above symptoms.

Sources: American Psychiatric Association. (2000). Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.); American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.).

DSM-IV-TR: Diagnostic and Statistical Manual of Mental Disorders: fourth edition, text revision. In use from 2000-2013.

DSM-5: Diagnostic and Statistical Manual of Mental Disorders: fifth edition. Released May 2013.