Cannabis (marijuana)
Key facts
- Cannabis is a common drug used in Australia.
- Marijuana and hashish (hash) are the most used forms of cannabis.
- People usually smoke cannabis or mix it with food (known as ‘edibles’).
- Using cannabis can lead to health problems such as addiction or depression.
- Medicinal cannabis is cannabis prescribed by a doctor to relieve the symptoms of a medical condition.
- Medicinal cannabis is different to cannabis that people buy on the street or through illegal means.
What is cannabis?
Cannabis is the general name for drugs like marijuana, hash and hashish oil that are made from the plant cannabis sativa. It’s the most used illicit (illegal) drug in Australia.
The different forms of cannabis are:
- marijuana — made from the plant's dried leaves and flowers (buds), and the most common form of cannabis. It is smoked in a joint (rolled cigarette) or bong (water pipe).
- hashish — the dried resin from the plant, usually mixed with tobacco and smoked or added to food, such as cookies or brownies
- hash oil — a liquid oil added to the tip of a joint or cigarette
- concentrates — cannabis extracts, usually dissolved in butane hash oil
Other names for cannabis include:
- marijuana
- yarndi
- pot
- weed
- hash
- dope
- 420
It is illegal to use, have, grow or sell cannabis in most states and territories in Australia. In the ACT, the cannabis laws have changed. Limited amounts of cannabis may be legally grown and used in the ACT — read more on legal use of cannabis in the ACT.
It is illegal to drive under the effects of cannabis in all Australian states and territories. .
Medicinal cannabis
Medicinal cannabis is cannabis prescribed by a doctor to relieve the symptoms of a medical condition. Medicinal cannabis continues to be researched and is increasingly used as a medicine in several health conditions including:
- chronic pain
- nausea and vomiting (for example, caused by chemotherapy)
- epilepsy
- multiple sclerosis (MS)
- palliative care
- cancer-related anorexia
Its supply is tightly controlled in Australia. Medicinal cannabis must be prescribed by a doctor.
Synthetic cannabis
Synthetic cannabis is a term used to describe a substance that is designed to mimic the effects of the active ingredient in cannabis (known as THC, or delta-9 tetrahydrocannabinol).
Synthetic cannabis is not legal in Australia. They are powdered chemicals that are mixed with solvents and sprayed onto herbs and sold in colourful packets. Not all forms of synthetic cannabis successfully mimic THC and they may be more harmful than real cannabis.
Synthetic cannabis is marketed under names such as:
- spice
- kronic
- northern lights
- aphrodisiac tea
- herbal incense
- potpourri
What are the effects of taking cannabis?
Cannabis can affect people differently. The same person may also have different experiences each time they use cannabis. Some factors that could influence the effect of cannabis are:
- how much you take
- how strong it is
- your size, height and weight
- if you’ve had cannabis before, and how often you have it
- if you take other drugs at the same time
- your personality
Cannabis can make some people feel ‘chilled out’, relaxed, happy and sociable, while other people may feel anxious or paranoid after taking cannabis.
People who take cannabis may:
- laugh a lot
- have heightened senses
- feel hungry
- feel drowsy
The effects are usually felt soon after is it smoked or vaporised, because the active ingredient is absorbed directly from the lungs to the bloodstream. If cannabis is eaten, it needs to be digested and can take between 1 and 3 hours to have an effect.
Cannabis can also cause side effects such as:
- balance problems
- rapid heart rate
- red, dry eyes
- dry mouth
- nausea
- memory problems
- slower reflexes
What are the risks using cannabis?
If you, or someone you known, is having suicidal thoughts and is in immediate danger, call triple zero (000). For help and support, call Lifeline on 13 11 14.
There are many risks with cannabis use including:
- toxicity and overdose
- unpredictable effects when mixed with other drugs
- dependence and withdrawal
- mental health risks, such as psychosis
People who have taken a lot of cannabis can experience:
There is evidence that links cannabis use with an increased risk for psychotic symptoms, schizophrenia and other mental health disorders.
Anyone who has an existing mental health condition or who has a close family member with conditions such as, psychosis, bipolar disorder or anxiety, should avoid cannabis.
Anxiety and panic symptoms are commonly seen in cannabis use, and daily use is linked with increased risk for suicide attempts especially among adolescents.
Vaping cannabis
Vaping cannabis means breathing in vapor from heated cannabis. Some people think it's safer than smoking marijuana because it might have fewer harmful chemicals. Vaping can still hurt your lungs and may make you dependent on cannabis. Vaping may also cause burn injuries.
Can cannabis cause long-term problems?
Regular cannabis users can become dependent and commonly report withdrawal symptoms, such as:
- depression
- anxiety
- sleep difficulties
- changes in appetite
People who use marijuana over long periods may have:
- social and financial problems
- family and relationship issues
- employment problems
- health issues when smoked, such as chest infections, upper respiratory tract cancers, chronic bronchitis and damage to airways
- problems with their memory
- psychotic symptoms, especially if they have schizophrenia or are at risk of psychosis
- suicidal thoughts
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
Can I become dependent on cannabis?
You could become dependent on cannabis if you are using it regularly.
Signs you are dependent include:
- using cannabis takes up a lot of time and energy
- cannabis is affecting your daily life
- you’re finding it hard to stop using cannabis
People who use cannabis regularly may experience withdrawal symptoms including:
- cravings (a strong urge) to use cannabis
- problems sleeping
- mood swings
- restlessness
- nausea
These problems are at their worst 2 to 4 days after quitting and usually last about 2 weeks.
If you are experiencing problems with withdrawal or feel your cannabis use is affecting your daily life, seek help and speak with your doctor.
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What if I use other drugs or alcohol together with cannabis?
Mixing cannabis with other drugs, such as alcohol, illegal drugs like cocaine or MDMA (ecstasy), or prescription medicines, can make the effects stronger and more unpredictable, which can then increase the risk of harm.
Resources and support
For more resources and support you can:
- call Lifeline on 13 11 14 for confidential crisis support
- call the National Alcohol and Other Drug Hotline on 1800 250 015 for confidential advice
- find out more about cannabis on the Alcohol and Drug Foundation website or email DrugInfo
- find out more about how drugs and alcohol can impact your health including where to find help and support
- call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.
Do you prefer to read in languages other than English?
- Positive Choices has information and resources on drug use for people from culturally and linguistically diverse backgrounds.
Looking for information for Aboriginal and/or Torres Strait Islander people?
- Positive Choices has information and resources on drug use for Aboriginal and Torres Strait Islander people and communities.
- The Alcohol and Drug Foundation has resources and drug facts for Aboriginal and Torres Strait Islander people.
Looking for information for sexually and gender-diverse people?
- Pivot Point offers resources and support on drug use for sexually and gender-diverse people.
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Last reviewed: April 2024