Healthy living

Cannabis

Cannabis is made from the dried flowering heads and leaves of a plant called Cannabis sativa.

Cannabis contains a complex mix of approximately 60 unique ‘cannabinoids’ along with many other chemical compounds. The main active ingredient responsible for the ‘high’ produced by cannabis is delta-9-tetrahydrocannabinol (THC).

Other related substances in cannabis include cannabidiol (CBD) and cannabinol (CBN), both of which have quite different pharmacological effects. These are collectively known as ‘cannabinoids’. Different strains of cannabis produce different amounts of these chemical substances.

What is medicinal cannabis?

‘Medicinal cannabis’ is a term that refers to legal, high quality and standardised products made from crude or raw cannabis. Crude cannabis is a difficult drug for doctors to prescribe because the dose and potency of the drug in each case is not tested or known.

Pharmaceutical preparations of cannabis use modified active components of cannabis in medical formulations, which maximise the therapeutic benefit and minimise side effects. Pharmaceutical preparations, such as a tablet, capsule or spray, mean the concentration can be standardised and the dose controlled.

Many medicinal cannabis products contain a combination of THC and CBD. Some products contain CBD only and others contain predominantly THC.

There may be different rules about the availability of cannabis products in other countries and products which are available without a prescription overseas may require a prescription in Western Australia. For example, products labelled as containing CBD Oil cannot be sold as dietary supplements in Australia. A CBD Oil product could only be legally obtained as a prescription medicine.

Differences between medicinal and recreational cannabis

Medicinal cannabis is legally produced under strict pharmaceutical conditions.

Doctors and pharmacists know exactly what the medicine contains.

The ingredients, potency and quality of illicit recreational cannabis are untested. Contamination with microbes, pesticides and heavy metals can occur.

In Australia, medicinal cannabis products come in a variety of forms including oils, sprays, tinctures capsules, creams, and dried herb. Medicinal cannabis products may be taken orally or sublingually (under the tongue), applied topically to the skin, or inhaled using TGA approved vaporisation devices.

By contrast, illicit cannabis is usually smoked. Smoking is a harmful way of using cannabis. People who smoke cannabis frequently develop the same breathing problems as people to smoke tobacco, such as cough, wheezing, excessive sputum and chronic bronchitis.

Cannabis sourced through illicit channels cannot be described as ‘medicinal cannabis’.

Benefits of medicinal cannabis

Currently, the scientific basis for using medicinal cannabis is incomplete. Research has shown some evidence medicinal cannabis may be useful in the following conditions:

  • treating certain childhood epilepsies
  • treating spasticity and pain in multiple sclerosis
  • treating chronic non-cancer pain
  • relieving chemotherapy induced nausea and vomiting
  • appetite stimulant for acquired immunodeficiency syndrome (AIDS).

Evidence suggesting medicinal cannabis may be beneficial in treating particular health conditions or symptoms does not mean it will necessarily be beneficial in treating other conditions or symptoms.

More information on the benefits of medicinal cannabis is available from the Therapeutic Goods Administration (TGA external site).

More research is needed

Larger, high-quality clinical trials are needed to investigate the potential benefits, limitations and safety issues associated with medicinal cannabis treatment.  Scientific research is underway to compare medicinal cannabis with standard medications and assist in identifying any potential interactions with other medicines.

If more studies provide evidence to support the use of medicinal cannabis, it is more likely doctors will feel confident in prescribing this treatment.

Side effects of medicinal cannabis

Like all prescription medicines, medicinal cannabis products can have side effects. These may include:

  • fatigue and drowsiness
  • dizziness and loss of balance
  • nausea and vomiting
  • appetite increase or decrease
  • dry mouth
  • diarrhoea
  • convulsions
  • feelings of euphoria (intense happiness) or depression
  • confusion
  • hallucinations or paranoid delusions
  • psychosis or cognitive distortion (having untrue thoughts)

The extent of side effects can vary between individuals and with the type of medicinal cannabis product used.

Cannabis may also interact with other medications to cause adverse effects. 

Medicinal cannabis may not be suitable for:

  • people with an active or previous psychotic, mood or anxiety disorder
  • people with unstable cardiovascular disease
  • women who are pregnant or breastfeeding.

Medicinal cannabis and driving

Products containing cannabis can impair attention, concentration, reaction time and judgement which affect a person’s fitness to drive and operate machinery. Studies have shown a significant proportion of drivers involved in traffic crashes test positive for cannabis.

It is therefore recommended that people using medicinal cannabis do not drive. Patients are advised to discuss driving whilst under treatment with medicinal cannabis with their doctor.

Cannabis may stay in your system anywhere from several days to several months after last use. Detection windows depend on the drug test used and other factors, such as whether you smoke or ingest marijuana on a regular basis.

In WA, it is an offence to drive with THC present in your system, regardless of whether the THC comes from prescribed legal medicinal cannabis or illicit recreational cannabis.

Legal status of medicinal cannabis

Who can grow medicinal cannabis legally? 

In February 2016, the Australian Government amended the Narcotic Drugs Act 1967 to allow cultivation of cannabis for medicinal or scientific purposes, under a national licensing scheme.

Some legally produced Australian medicinal cannabis products are now available.

The changes do not legalise the growing of cannabis for non-medical purposes.

For more information visit the Office of Drug Control (external site).

Can I grow my own medicinal cannabis legally?

No, there is no change to Commonwealth or Western Australian laws around cultivation for recreational use. The recent changes to Commonwealth laws are not designed to permit the personal or home cultivation of cannabis for use in medical conditions. 

Does the legalisation of medicinal cannabis mean it is legal to smoke cannabis?

No, cannabis is still a highly regulated drug in Australia and its use and supply is controlled or prohibited by a number of Commonwealth and State and Territory laws.

As it is still illegal to use recreational cannabis, you cannot claim smoking cannabis is for ‘medicinal’ purposes.

Who can prescribe and supply medicinal cannabis legally?

Any doctor in Western Australia can prescribe medicinal cannabis if they believe this treatment is suitable for you and provided they have the required Government approvals. Prescriptions for medicinal cannabis can be dispensed at any pharmacy in Western Australia.

Obtaining medicinal cannabis

How can I access medicinal cannabis in WA?

Medicinal cannabis products are prescription medicines and have been available in Australia since early 2017.  It is recommended you talk to your doctor about whether medicinal cannabis would be beneficial for you.

A range of imported products and some locally produced products are available. Your general practitioner and your medical specialist are best placed to select the most appropriate product for your medical condition.

General practitioners can initiate treatment with medicinal cannabis for most patients. If the patient has a history of drug dependence, the support of a medical specialist is required. Prescribing for children and young people also needs the involvement of a specialist.

Medicinal cannabis products that contain THC are classed as Schedule 8 medicines (also called Controlled Drugs). Almost none of the available medicinal cannabis products are registered with the Therapeutic Goods Administration (TGA) as products which can be sold as ‘therapeutic goods’ in Australia. This means your doctor will need approval from the TGA. For more information visit the Therapeutic Goods Administration (external site)

To obtain approval, doctors need to complete an online application via the TGA website. Decisions about applications usually take two working days.

Once your general practitioner or specialist has received the required approvals, they can write a prescription for you. You can take this prescription to any pharmacy for dispensing.

Is there list of doctors who prescribe medicinal cannabis products?

No, in WA any medical practitioner can prescribe medicinal cannabis if they believe it is clinically appropriate and they have the necessary approvals. 

Cost of medicinal cannabis products

Currently no medicinal cannabis products are funded under the Pharmaceutical Benefits Scheme (PBS). Medicinal cannabis must be dispensed as a private prescription and the patient will have to pay the full cost of the product. The cost varies from one product to another.

Can cannabis-based products be imported from overseas?

Patients located within Australia are not allowed to import medicinal cannabis products themselves. Further information is available from the TGA (external site).

The Office of Drug Control (ODC) publishes a list of importers and manufacturers (external site)  of medicinal cannabis products, to assist in identifying products currently available in Australia. Products vary in composition and strength. Which product is best for you is something to discuss with your doctor.

The ODC has information about importation of hemp seeds or hemp seed oil (external site), which are allowed in foods.

Can I bring medicinal cannabis to Australia when returning from overseas?

If you are travelling to Australia, you are able to carry up to three months’ supply of medicines for yourself or a passenger in your care. You must have a prescription from a medical practitioner and the medicine must be obtained in accordance with the prescription. Details of the requirements are available from the TGA (external site).  

More information


Acknowledgements

Disaster Management, Regulation and Planning, Public Health Division


This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.

See also

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