Substance use disorder

Substance use disorder is the medical term for having a drug problem that affects thinking and behaviour.

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What is substance use disorder?

Substance use disorder can be caused by too much alcohol, tobacco, cannabis, hallucinogens (e.g. magic mushrooms, acid), inhalants, opioids (e.g. heroin, codeine), sedatives (e.g. benzodiazepines), stimulants (e.g. methamphetamine, cocaine) or other drugs.

Substance use disorder is the medical term for having a drug problem that affects thinking and behaviour. It involves the build-up of tolerance to the drug and symptoms of withdrawal when the drug levels in the body fall.

How common is substance use disorder?

Just over one in four Australian males aged 16-85 years have substance use disorder at some point in their lives. At any one time, 4% of Australian males aged 16-85 years have substance use disorder. Substance use is twice as common in males than in females.

What are the symptoms of substance use disorder?

In addition to the criteria used to diagnose substance use disorder, there are other signs and symptoms of substance use disorder, which can be different depending on the substance. 

What causes substance use disorder?

There are complex genetic, environmental, psychological and social causes of substance use disorder.

Substance use disorder involves changes in the ‘wiring’ of the brain, caused by substance use, that drives ongoing use of the substance. 

Not everyone who uses drugs develops substance use disorder, and some people recover while others develop greater severity.

Personal factors such as childhood experiences, the age at which substance use begins and personality contribute to the development of substance use disorder, and are influenced by family and community support, disorder in day-to-day living, and socioeconomic disadvantage.

The availability of drugs, and how they act in the body, also influences whether someone develops substance use disorder.

How is substance use disorder diagnosed?

To diagnose substance use disorder, your doctor will ask you some questions about your substance use and your physical and mental health, and they might perform a physical examination.

There are no laboratory tests needed to diagnose substance use disorder, but your doctor might order tests to work out how much your health has been affected by your substance use, or to track progress during treatment.

How is substance use disorder treated?

Treatment for substance use disorder varies from person to person, depends on the severity of the disorder, and the substance(s) being used. Your doctor will work with you to identify the right treatment for you and track your progress.

Counselling and medication together can be more helpful than either type of treatment alone.

In addition to treatment for substance use disorder, many people also need treatment for diseases caused by substance use. Treatment of physical or psychological health issues might be necessary.

What does substance use disorder mean for my health?

Substance use affects many parts of the body, including the brain, heart, lungs, liver, blood and the immune and hormonal systems. There are also widespread psychological effects.

Health problems arising from substance use disorder will depend on the substance(s) being used, the amounts used and how often, and personal characteristics.

Substance use disorder is similar to chronic diseases like diabetes or cardiovascular disease; rather than being cured, most people experience periods of remission and relapse depending on individual circumstances.

The longer someone has been in remission, the less likely there are to relapse.

What should I do about substance use disorder?

It’s best if your doctor knows about anything that might affect your health, including substance use, so you should tell them about it and answer any questions honestly.

The Alcohol and Drug Foundation can help you find services to help with substance use and provide information that’s relevant for anyone.
Substance use disorder

Did you find this page helpful?

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