Medicinal cannabis, also known as medicinal marijuana, has received much attention over the last few years. Its use and acceptance in treating a variety of conditions continues to evolve, along with research to support its use in a medical context.

medicinal cannabis

Research

Several studies have found that the most common reason patients turn to medicinal cannabis is for the treatment of chronic pain. While research is still developing, there have been several studies showing that medicinal cannabis can be beneficial in treating some types of chronic pain. Evidence shows that medicinal cannabis is suited to alleviating pain, but its effectiveness and dosage requirements research is still limited. There is also evidence showing that patients are replacing conventional pain medications, such as opioids, with cannabis. A study investigating cannabis-using patients found that it was associated with:

  • A 64% decrease in opioid use

  • Better quality of life in patients with chronic pain

  • Fewer medication side effects and medications used

It is recommended that medicinal cannabis only be used when approved treatments have been tried and have failed to manage conditions and symptoms.

History

Cannabis is one of the oldest documented herbal medicines and has been used for at least 5000 years. Around the 1st century, the ancient Chinese used it to treat rheumatic pain, constipation, female reproductive disorders, and malaria. Ancient Indians also used cannabis to relieve headaches, insomnia, gastrointestinal disorders, and as pain relief during childbirth.

Eventually, cannabis spread throughout Europe and the Americas in the mid-19th century, with the US first listing it as a sedative, analgesic and anti-convulsant in 1845. Its herbal properties grew in popularity, and it was not long until it was used to treat a multitude of ailments, including headaches and migraines, eye strain, menopause, brain tumours, neuralgia, gastric ulcers, uterine problems, menstrual cramps, chronic inflammation, acute rheumatism, tingling, and to help relieve dental pain. Increased public consumption was the result of the more commercial production of medicines in the late 1800s.

However, the early 20th century saw an overall decline in herbal remedies - including cannabis - as barbiturates, aspirin, and opioids became more mainstream. The lack of regulation, along with the criminal associations of cannabis use, led to a further decrease in consumption and its ultimate criminalisation in Australia and many other countries.

Since the 1940s, research and experimentation into cannabis' pharmacological properties continued, which led to some medical sectors advocating to make medicinal cannabis legal. In 1996, California became the first US state to legalise medicinal cannabis, with Canada following in 2003. Many other countries have now legalised medicinal cannabis, including Australia.

How does medicinal cannabis work?

It is believed that medicinal cannabis is effective in treating various illnesses by acting upon the body's endocannabinoid system - a communications system in the brain and body than affects mood, memory, sleep, and appetite. Over 100 cannabinoids, which are naturally occurring compounds which are also made in our bodies, have been identified in cannabis. Endocannabinoids are also present in our peripheral and central nervous systems where they act to reduce pain.

The two major cannabinoids in cannabis that have been found to have medical benefits are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is a compound that has strong psychoactive effect (eg. changes the way someone thinks, feels and even behaves), which causes a person to get 'high'. While many are aware of the euphoria, relaxation and sleepiness associated with THC, t has also been found to have analgesic (pain relief), anti-inflammatory and anti-oxidant properties. In addition, it has been found to prevent or reduce vomiting. CBD, on the other hand, is believed to have anti-psychoactive effects which controls or moderates the 'high' caused by THC. It is thought that CBD may reduce some of the other negative effects caused by THC, such as anxiety.

recreational cannabis vs medicinal cannabis

Recreational cannabis (marijuana) and medicinal cannabis are both made from the plant cannabis sativa. The two main cannabinoids in cannabis are THC and CBD. Generally, THC is found at higher concentrations than CBD, unless the ratio is altered deliberately. Medicinal cannabis products can contain high or low levels of THC or CBD, in various combinations and with other cannabinoids. The efficacy of cannabis for various medical conditions will depend upon the types and amounts of cannabinoids in the product.

Medicinal cannabis is highly regulated and contains very controlled amounts of THC and CBD, which are known by the doctor when prescribing them. With recreational cannabis, the quantities of these components are often unknown, and vary between batches and suppliers depending on the conditions in which the plan was grown, such as soil quality, bacterial and fungal contamination, the use of herbicides, pesticides, insecticide, water, light, soil availability or quality, temperature, bacterial or viral contamination, animal waste, insects, toxic chemicals, active compounds, and heavy metals. There is no guarantee of product quality or that the product is free from other toxins, or that it even contains the components needed to provide a medicinal effect. Cannabis smoke associated with recreational cannabis also contains significant amounts of toxic chemicals, including ammonia, hydrogen cyanide and nitric oxide.

What does medicinal cannabis look like?

In Australia, medicinal cannabis may be in the form of: ora capsules or oils, oral lozenges, oral sublingual spray, vaporisation disks, topical cream, vaginal pessaries and vaginal creams.

Potential side effects

Like all prescribed medications, medicinal cannabis can have side effects. The extent of these side effects, however, ca vary depending upon the type of medicinal cannabis product used, and between individuals. Generally, the side effects of CBD-rich products are less than those for high-THC products.

The side effects of medicinal cannabis are still being studied. Currently known side effects include:

  • Fatigue and sedation

  • Feelings of euphoria (intense happiness)

  • Depression

  • Drowsiness

  • Vertigo (dizziness)

  • Difficulty concentrating

  • Problems with balance

  • Problems with thinking and memory

  • Nausea and vomiting

  • Fever

  • increased or decreased appetite

  • Dry mount

  • Diarrhoea

  • Convulsions

  • Confusion

  • Hallucinations

  • Paranoid delusions

  • Psychosis

  • Cognitive disorder (having thoughts that are not true)

  • Reduced semen quality

Who should not use Medicinal cannabis?

Medicinal cannabis is not suitable for everyone. In particular, they are not recommended for patients who:

  • Have a previous psychotic or concurrent active mood or anxiety disorder

  • Are pregnant, planning to become pregnant, or breastfeeding

  • Have unstable cardiovascular disease

Medicinal cannabis may be more likely to cause negative effects in patients with neurological conditions.

There is also very limited evidence regarding how it interacts with other medications, so caution is advised if medicinal cannabis is to be taken with other medications and complementary medicines. Talk to your prescribing doctor for guidance.

COST

Cost for the medicinal cannabis product star from $375 per month, and may vary depending on the dose, the frequency of treatment and formulation utilised. The initial consultation fee with a doctor at Metro Pain Group will be $300-350. Medicare offer a rebate of $65-130 for this visit. There will be several review appointments required to monitor the patient's treatment. The cost for review appointments will be $80 with a Medicare rebate of $21-60.

Precautions

Medicinal cannabis can impair driving ability, and THC can be detected in urine for a number of days after the last dose. Consequently, medicinal cannabis patients should avoid driving motor vehicles or operating machinery. In Australia, drug-driving is a criminal offence and carries harsh penalties, including heavy financial penalties and the loss of one's license. Patients should consult with their doctor to understand the impact of cannabis treatment on driving, and how to drive safely within the law.

As there is no guidance on appropriate or safe doses, it is recommended that caution be exercised and that initial doses are low, and if necessary, slowly increased. Low start doses are particularly important for people with memory and thinking difficulties, liver and kidney disease and weakness and wasting of the body due to severe chronic illness.

ACCESS

Medicinal cannabis is tightly regulated in Australia and is therefore subject to legal requirements. The Therapeutic Goods Administration (TGA) regulates the supply of medicinal cannabis in Australia. Patients must access the product through their doctor, who must meet certain requirements, obtain permits and comply with relevant and varying state laws.

Medicinal cannabis is not kept on the premises, but is dispensed via the Australia Medicinal Cannabis Service (AMCS), an external organisation that provides clinical support product formulation and technology services to medical clinics prescribing cannabis.

To obtain access, a patient must be assessed by a doctor and sign relevant consent and agreement forms, including several questionnaires over the duration of the treatment, and consent for information sharing between MPG, AMCS and regulating bodies. Please refer to our privacy policy for further information.

Rescheduling and enquiries

Should you have any enquiries or require rescheduling of your procedure, please notify the Clinical Support Team on 03 8548 0339.