Medical cannabis is prescribed more frequently for chronic pain than for any other condition – almost 60% of all medical cannabis prescriptions in Australia are issued to people struggling with pain.
While chronic pain may seem simple, in reality it’s a complex and varied condition thought to affect 3.6 million Australians, whether as pain from an injury or accident, neuropathic pain, fibromyalgia, arthritis and more.
This post will explore what chronic pain is and how medical cannabis is being used as a promising alternative treatment for this often debilitating condition.
What Is Chronic Pain?
At a very basic level, chronic pain is defined as any pain that lasts for longer than 3 months. Pain itself is a complicated neurobiological response governed by our nerves that basically tells the body to try and avoid whatever is causing the pain. In cases of chronic pain, incomplete healing or nerve damage can lead to the sensation continuing for months or even years.
There are no hard and fast rules when it comes to how people experience chronic pain. For some it will be sharp and insistent, for others a dull throb. Some people will feel the pain constantly, while others can go days or weeks between attacks. They may also have other symptoms, such as feeling tired, fatigued or weak. Many people with chronic pain struggle to sleep and can lose their appetite.
As a result, people experiencing chronic pain often struggle to maintain regular activities like going to work, exercising and socialising. This can negatively affect their physical and mental health – people living with chronic pain have significantly elevated rates of anxiety and depression.
Causes Of Chronic Pain
The most common cause of chronic pain is injury or illness. For example, back injuries are a common cause of chronic pain. Surgery is another; many people experience post-surgery pain long after healing. Illnesses like cancer and arthritis are other frequent causes of chronic pain.
Another significant cause of chronic pain is what’s known as neuropathic or nerve pain. If nerves are damaged by an injury or illness, they can start to send pain signals even when there’s no other physical symptoms. Underlying health conditions can also cause chronic pain, including fibromyalgia, endometriosis, chronic fatigue syndrome and inflammatory bowel disease.
There’s still a lot we don’t understand about chronic pain, especially when it isn’t caused by a specific injury or illness. But we do know that there are complex interactions between physical and emotional pain. This means that every person experiences chronic pain differently and our life experiences and mental health can influence how much pain we feel.
Chronic pain affects almost 1-in-6 Australians. This September is Pain Awareness Month and we’re donating money to Chronic Pain Australia, to help them continue their vital work advocating for those living with chronic pain. If you want to get involved, you can make a donation here.
Treating Chronic Pain With Medical Cannabis
If your pain is the result of injury or illness, the first line treatment will usually be painkillers – and in particular opioids – alongside physical therapy. For neuropathic pain, where opioids are typically less effective, treatments may be targeted towards emotional management, including cognitive behavioural therapy and antidepressants.
However, for many patients these treatments either don’t fully relieve the pain or cause difficult side effects.
As medical cannabis becomes increasingly accepted an increasing number of patients are exploring whether it could help manage their chronic pain. In Australia, medical cannabis is still considered an alternative treatment, meaning that patients must have tried other first line treatments before it can be prescribed.
Patients are typically prescribed dried flower, which is vaporised and inhaled, vape carts or oil, which can be swallowed.
How Does Medical Cannabis Treat Pain?
There are two primary cannabinoids in cannabis: tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is the compound that produces marijuana’s psychoactive effects (commonly known as a “high”), while CBD acts on different parts of the body to produce a therapeutic response without the psychoactive effect.
Both THC and CBD (along with the more than 100 minor cannabinoids) act on your body’s endocannabinoid system, a network of receptors that help regulate everything from your metabolism to your liver function, immune system and pain response.
However, THC & CBD interact with your endocannabinoid system in different ways. THC primarily binds to CB1 receptors, which are located in the brain and central nervous system. Meanwhile, CBD predominantly binds to CB2 receptors, which are located throughout the body’s immune tissues.
Both THC and CBD are being explored for pain management and emerging research suggests that both could have a role to play – one more focussed on the mind, one on the body.
Medical Cannabis For Chronic Pain: What Does The Research Say?
A number of systematic reviews have been done of the existing evidence regarding the use of medical cannabis to treat chronic pain.
A 2021 review published in the BMJ pointed to a small but statistically significant improvement in pain levels, physical activity and sleep quality among medical cannabis users. Similarly, a 2022 review found that products with high THC-to-CBD ratios produced short-term improvements in pain, albeit with commonly reported dizziness and sedation.
However, as is the case with all areas of medical cannabis study, these reviews emphasise that the research remains limited and more detailed studies will improve our understanding of exactly how cannabis should best be used and in what contexts.
Medical Cannabis & Improved Quality Of Life
While the debate around medical cannabis’ analgesic (or pain-relieving) effects continues, the shorter story is that hundreds of thousands of patients use and continue to use medical cannabis and often report significantly improved outcomes.
An Australian study tracked more than 3000 patients for four years to gauge how using medical cannabis affected their quality of life. The authors found that medical cannabis use was associated with “significant improvements” in reported quality of life, which were mostly sustained over time.
Similarly, in a 2023 survey of more than 2900 chronic pain patients conducted by Montu, almost 9-in-10 reported a positive effect on their quality of life, while 96% found cannabis to be a somewhat or very effective treatment for pain, with an average reduction in reported pain of more than 30%.
How do we explain this difference between the small improvements seen in official studies and broader quality of life surveys? One part of it could be the early stage of much of the research into cannabis’ pain-relieving properties – better studies with better questions and better treatments could start joining the two.
Another part of it could be the complex nature of pain itself: cannabis is typically experienced as a mood-enhancer and the way we experience pain is largely driven by how we feel. Cannabis may help those who are fixated by or depressed about their pain to pay it less attention or treat it less seriously. These may be difficult effects to quantify, but should be key questions to be considered in future research.
What We Know About Using CBD Oil For Pain
While a lot of the most promising research around medical cannabis and pain focuses on THC-dominant products, some patients may be unable or unwilling to experience the psychoactive effects of THC – what’s commonly known as the “high”.
Fortunately, there have also been studies done into using CBD oil to treat pain. CBD or cannabidiol is the other major cannabinoid found in the cannabis plant and is also known to affect the endocannabinoid system.
As far as the research goes, it’s still early but there are some positive signs emerging. For instance, a 2021 survey of 2,701 people with fibromyalgia found that CBD use was generally effective at reducing pain, however the authors stated that more rigorous studies are required to better understand if this is a consistent effect.
When it comes to cancer-related pain, one review suggested that CBD may be a useful option to reduce cancer pain and ease chemotherapy side effects, while for arthritis, a study into knee pain caused by osteoarthritis suggested that CBD was more effective in reducing pain than a placebo.
Side Effects Of Using Medical Cannabis For Pain
Like all medications, medical cannabis can have side effects.The extent of these side effects will depend on what type of medical cannabis you’ve been prescribed, your dose and how your body reacts to the medication. CBD-dominant products such as isolate CBD oils generally have fewer side effects than THC products.
Side effects associated with either CBD or THC may include fatigue, vertigo, nausea, vomiting, fever, decreased or increased appetite, dry mouth and diarrhoea. Most of these side effects are rare or minor in effect – medical cannabis is usually well-tolerated. However, if your chronic pain is the result of an injury or surgery, vertigo and fatigue can increase the risk of falls or other accidents so should be carefully monitored.
Medical Cannabis & Pain: Taking The Next Step
If you think that medical cannabis might be able to help with your pain management, book a consultation with a doctor at a medical cannabis clinic or your local GP. They’ll be able to explain the potential benefits and risks and work out a treatment plan that suits your particular symptoms and experience.
If you still have questions or want to know more, book a spot at the Pain Awareness Month: Chronic Pain & Plant Medicine webinar on September 27, hosted by Chronic Pain Australia and Alternaleaf, and featuring an extra special guest speaker, as well as a Q&A with an Alternaleaf nurse.