Medicinal Cannabis

Medicinal Cannabis

New Hope for Seizure Control

While up to 70 percent of people with epilepsy are able to obtain seizure control with antiepileptic drugs (AEDs), around about 30 percent continue to have seizures despite the availability of many antiepileptic drugs. Some people may have very few seizures whilst others may have many severe and damaging seizures on a daily basis.

No matter how many seizures a person is having, epilepsy can significantly affect quality of life. However, the treatment gap has led people to seek alternatives, including medicinal cannabis.

Research is finding that compounds derived from the cannabis plant can reduce the severity and frequency of seizures in some people, especially in children who have catastrophic epilepsy disorders.

What is Medicinal Cannabis?

For centuries, the cannabis plant has been considered to have therapeutic properties including anticonvulsant effects.

Cannabinoids are substances in cannabis that act on cells in the body (called cannabinoid receptors) to cause some effect. Two major ingredients include:

  • Tetrahydrocannabinol, or THC, which causes the psychoactive effects of ‘getting high’. THC may be harmful for people with epilepsy and put them at increased risk of psychiatric problems such as psychosis
  • Cannabidiol, or CBD is found in cannabis stalks and flowers and does not contain mind-altering properties. It has shown some positive effects on certain body systems and may potentially help control seizures.

Unlike recreational cannabis, medicinal cannabis does NOT contain the properties that cause the effect of getting ‘high’ or ‘stoned’. In fact, CBD is thought to have an anti-psychoactive effect that controls or moderates the ‘high’ caused by THC, and may even reduce some of the other negative effects that people can experience from THC, such as anxiety.

For more comprehensive information go to Cannabis 4 Epilepsy

What Recent Research Tells Us

Randomised controlled trials are underway for children and adults using different formulations of cannabidiol (CBD).

There is evidence that cannabis can be helpful in controlling seizures in some cases, especially for difficult to control syndromes like Dravet Syndrome in children and Lennox-Gastaut Syndrome (LGS).

In 2017, an international trial testing cannabidiol in children with Dravet Syndrome – a complex disorder caused by a rare genetic mutation where children suffer medication-resistant seizures and a high death rate, was conducted.

In the Trial of Cannabidiol for Drug-Resistant Seizures in the Dravet Syndrome published in the New England Journal of Medicine in 2017, 120 children or young adults remained on epilepsy medications as well as taking either a cannabidiol liquid/oil (Epidiolex®) or a placebo.

Study details and findings:

  • The frequency of seizures was measured over 14 weeks.
  • Of those given medicinal cannabis, more than 40% had their seizures halved.
  • 5% became seizure free.
  • 93% of the treatment group suffered side effects, compared with 74% in the placebo arm. The most common of these were vomiting, fatigue and fever. These side effects were generally not considered serious, although eight patients in the cannabidiol group did drop out of the trial.

In another study Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial published in The Lancet Neurology in 2016, 214 people received oral cannabidiol over a 12-week treatment period.

Study details and findings:

  • Patients involved in the study (aged 1–30 years) had severe childhood-onset, treatment-resistant epilepsy and were receiving stable doses of antiepileptic drugs before study entry.
  • Results showed a median 36.5% reduction in monthly motor seizures, with the median monthly frequency of motor seizures falling from 30 motor seizures a month at the study’s start to 15.8 over the 12 weeks.
  • Unwanted  side effects were reported among patients, including drowsiness, decreased appetite, diarrhoea, fatigue and convulsion.
  • Most side effects were mild to moderate and short-lived, but 20 patients had serious adverse events related to CBD use –most commonly status epilepticus (seizures that last too long or are too close together).

Cannabidiol in patients with seizures associated with Lennox-Gastaut syndrome (GWPCARE4): a randomised, double-blind, placebo-controlled phase 3 trial.

In 2018, this trial was done to appreciate the potential effects of CBD in controlling drop seizures in people with Lennox-Gastaut syndrome (a childhood onset seizure disorder associated with encephalopathy which usually is multi-drug resistant).

Study details and findings:

There was 43.9% reduction of drop seizures in CBD group and 21.8% of the reduction in the people who were in the placebo group. Besides drop seizures, the frequency of other types of seizures was also reduced drastically which reflected a wide spectrum of effects of CBD in controlling different types of seizures.

The most common unwanted side effects (in >10% of cases), though mild to moderate in severity, including sleepiness, diarrhoea, and decreased appetite were seen in 86% of patients who were in CBD group and 69% of patients who were in the placebo group.


Despite the anecdotal and early scientific research into cannabis for medical use, anyone using cannabis should be aware of the interactions it might have with their medication, as well as information on safe dosage and side effects.

Is Medicinal Cannabis Legally Available in Australia?

In early 2017, the Federal Government loosened laws to allow easier importation of medicinal cannabis from suppliers overseas. Even though domestic cultivation became legal in 2016, an adequate local supply in Australia has yet to be produced.

Access to medicinal cannabis involves a much more complicated process than with most other medicines. Most medicinal cannabis products are ‘unregistered products’ and therefore do not appear on the Australian Register of Therapeutic Goods (ARTG). This means that you can’t simply go to a doctor, obtain a prescription, and fill it at a pharmacy as you would with conventional registered medicines.

A doctor must either be an ‘Authorised Prescriber’ or be prepared to make an application on behalf of their patient through the TGA ‘Special Access Scheme’.

Doctors need to be able to show that the drug would be of benefit for their  patient and the application processes are stringent.

Read here about accessing medicinal cannabis

Current laws

In addition to a doctor prescribing the treatment, the legal use of cannabis for medical purposes differs by States and Territories.

  • Federal Government
    The Federal Government relaxed medicinal cannabis restrictions in March 2018 and has passed legislation legalising the cultivation of cannabis for medicinal purposes.
  • Queensland
    Legal by prescription from specialists for use by patients with a range of conditions including MS, epilepsy, cancer, and HIV/AIDS. See Queensland Health for details.
  • Tasmania
    Controlled Access Scheme began in 2017 to allow patients to access unregistered medicinal cannabis. No legislative changes were required in Tasmania. (See Tasmanian Department of Health for details.)
  • New South Wales
    Legal for use by adults with end-of-life illnesses. In 2017, the state government announced that 40 children in the state with the most severe cases of drug-resistant epilepsy would have access to a cannabis-based treatment under a compassionate access scheme. See NSW Government’s Centre for Medicinal Cannabis Research and Innovation for details.
  • ACT
  • People who fall under category 6 illnesses within certain criteria as of 2017 – See ACT Health for details on what this means.
  • Western Australia
    Legal by prescription from doctors under certain conditions, from November 2016: Misuse of Drugs Act 1981. (See WA Department of Health for details.)
  • Victoria
    Legal for use by children with severe, treatment-resistant epilepsy. See Health.Vic for details.)
  • Northern Territory
    The Australian Government Department of Health regulates therapeutic medicines containing cannabinoids through the Therapeutic Goods Administration – access is restricted to patients with certain medical conditions (See NT Government or Department of Health for details).
  • South Australia
    Legal by prescription from authorised doctors under certain conditions, from November 2016. (See SA Health for details).

Epilepsy Action Australia’s Position

A survey conducted by Epilepsy Action Australia revealed that 14% of 983 people surveyed were currently using cannabis-based products for medicinal purposes. Of these 86% reported that cannabis used for medicinal purposes was helpful in managing their seizures.

Epilepsy Action believes in a thoughtful and thorough pharmacologic and clinical investigation into cannabis to confirm or disprove its safety and antiepileptic potential.

We are at the forefront of advocating for increased research into this area of new hope, and assisting through various Government and University constituted Boards and Steering Committees.

More Information

  • Cannabis 4 Epilepsy is a website dedicated to providing people with the most current information available about cannabis for epilepsy.
  • MyEpilepsyKey – detailed information about the endocannabinoid system, cannabinoids, cannabis based medicines, the therapeutic use of cannabis in epilepsy, educational videos, books and links to Australian and International patient and advocacy groups
  • Epilepsy Action Australia also publishes regular email updates on the progress of all aspects of medicines
  • United in Compassion – Australia

Cannabis Clinics

Research articles

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