Medicinal Cannabis – The Basics

A brief history of medicinal cannabis

The plant cannabis (also known by the names marijuana / marihuana, ‘weed’, ‘pot’, ‘hash’ and many others!) has a long history as a food, resource and medicine in human culture, with records stretching back over 4,000 years – making it one of the oldest medicines on record.1,2 It’s thought to have originated in Central Asia and was used by nearly all known ancient cultures, including Egyptian, Greek, Roman, Indian and Chinese societies.3

Areas of use

Medicinal cannabis has been used in both ancient and modern times to help treat many different conditions, including2,4:

  • Chronic pain
  • Sleep, mood disorders and mental health
  • Nausea and vomiting
  • Epilepsy
  • Pain and spasticity caused by multiple sclerosis

Medical research into the use of cannabis is currently limited, but more and more studies are now being performed on the use of medicinal cannabis to treat these and other conditions.

How medicinal cannabis works

More than 100 different cannabinoids (cannabis-specific chemicals) have been identified in cannabis, but two in particular are medically important: delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD).3

THC and CBD act through the endocannabinoid system, and have different effects on the body5,6:

THC

CBD

Psychoactive (can make you feel ‘high’)
Anti-psychoactive (moderates the ‘high’)
Pain-relieving and anti-inflammatory properties
Pain-relieving and anti-inflammatory properties
Reduces nausea and vomiting
Reduces anxiety
Increases appetite
Anti-convulsant properties
Effects on sleep and memory
Anti-psychotic

Medicinal cannabis products have different actions depending on the ratio of THC to CBD that they contain. CBD acts to balance out some of the negative effects of THC, so combining THC with CBD can allow patients to receive higher doses of THC with a reduced risk of unwanted side-effects.5,6

The endocannabinoid system

The endocannabinoid system is spread right throughout the body and influences many different areas – in particular the immune and nervous systems. The chemicals THC and CBD interact with this system by binding to the endocannabinoid receptors CB1 and CB2, which are expressed by different tissues in the body.7

The Body’s endocannabinoid system8,9

Areas of major expression


Image adapted from Zhou and Kumar, 20188 and www.cannainsider.com/reviews/the-endocannabinoid-system/

The endocannabinoid system has been shown to have important roles in regulating many different bodily functions, including sleep, appetite, pain sensation and inflammation.7

The different forms of medicinal cannabis

Medicinal cannabis can be taken in different ways and is available in a range of THC:CBD ratios. The most common forms are oils or capsules to be taken orally, or dried plant material for inhalation (used with a vaporiser). These different forms act on the body at different speeds – for example, inhaled THC/CBD is active much faster than THC/CBD taken orally.10

What to expect from treatment

When first starting medicinal cannabis, doses are carefully increased from a minimum amount to allow the body to get used to the treatment’s effects. Treatment is tailored for each person’s needs, with different THC:CBD ratios being used depending on the symptoms being treated.

Using medicinal cannabis may cause side effects, but just like any other medicine these will be carefully monitored by a doctor.

If you are a healthcare professional and would like to learn more about medicinal cannabis, you can visit Medic for free online education on the safety, clinical considerations and areas of use of medicinal cannabis.

• Accredited in Australia by the RACGP and ACRRM


Visit Medic

Visit our FAQ page to view commonly-asked questions on accessing medicinal cannabis.

For information and support accessing medicinal cannabis in your country, please register with Althea Concierge

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References: 1. Russo EB. Chemistry & Biodiversity 2007; 4: 1614-48. 2. Zuardi AW. Braz J Psychiatry 2006; 28: 153-7. 3. Grof CPL. Br J Clin Pharmacol 2018; 84: 2463-67.

4. Lafaye G, et al. Dialogues Clin Neurosci 2017; 19: 309-16. 5. Russo E & Guy GW. Med Hypotheses 2006; 66: 234-46. 6. Mechoulam R & Parker LS. Annu Rev Psychol 2013; 64: 21-47.

7. Lu HC & Mackie K. Biol Psychiatry 2016; 79: 516-25. 8. Zou S & Kumar U. Int J Mol Sci 2018; 13: E833.

9. Human Protein Atlas – CNR2. Accessed from: https://www.proteinatlas.org/ENSG00000188822-CNR2/tissue Accessed on: 12 April 2019. 10. Kumar RN, et al. Anaesthesia 2001; 56: 1059-68.