Arthritis patients have been turning to medicinal cannabis for relief from pain and other symptoms for many years.
Now that medicinal cannabis is legal in New Zealand and other parts of the world, there’s growing interest in its potential as a treatment for arthritis symptoms.
As the world’s leading cause of chronic disability, arthritis has a significant impact on quality of life, making everyday tasks difficult, uncomfortable, and sometimes impossible.
In 2018, approximately 670,000 people aged 15 or over in New Zealand were living with at least one type of arthritis (about 17% of the population aged 15 or over).
Globally, millions of people are living with arthritis every day.
While there’s no cure for arthritis, there are several treatments designed to help relieve common symptoms, such as joint pain and stiffness, inflammation and muscle weakness.
If you’re not getting the results you want from conventional treatments, you’re experiencing adverse side effects, or you simply want to try a more natural alternative, you may want to consider using medicinal cannabis.
You’ve probably heard from others in the arthritis community that medical cannabis can help to relieve symptoms.
But before you talk to your doctor about getting a medicinal cannabis prescription, let’s take a look at what the research says about cannabis and arthritis.
What is arthritis?
You might think arthritis is just “normal wear and tear” in the human body or an old person’s disease. However, it’s not that simple.
“Arthritis” is actually a blanket term for joint pain or joint disease.
There are more than 100 different types of arthritis and related conditions and they can affect people of all ages, genders, and ethnicities. Although, women are more likely to be affected than men.
You can be diagnosed with arthritis at any age, but most types are more common in older people. It can develop suddenly or gradually and affect one or more joints.
The most common types of arthritis are osteoarthritis and rheumatoid arthritis.
Osteoarthritis occurs when the protective cartilage that cushions your joints wears down over time and most commonly affects the hands, knees, hips and spine.
Rheumatoid arthritis is an autoimmune disease that causes the immune system to attack the joints between your bones, which can lead to severe inflammation and joint damage.
Other common types of arthritis and related conditions include gout, psoriatic arthritis, fibromyalgia, ankylosing spondylitis, and lupus.
Treatments for arthritis
The most common treatments for arthritis fall into four categories: Therapy, Lifestyle changes, Medications, and Surgery.
- Therapy: Hydrotherapy, massage, stretching, acupuncture
- Lifestyle changes: Exercise, weight loss, hot and cold therapy, yoga, tai chi
- Medications: Painkillers, nonsteroidal anti-inflammatory drugs (NSAIDs), disease-modifying antirheumatic drugs (DMARDs), counterirritants
- Surgery: Hip, knee and joint replacements
Each type of arthritis and each patient may require a different treatment approach.
Given the prevalence of adverse side effects from conventional painkillers and NSAIDs and a growing preference for more natural medicines, more arthritis patients are looking to medicinal cannabis to treat their symptoms.
Medical cannabis and arthritis: What does the research say?
As far back as 2000 BC, Chinese healers claimed that medicinal cannabis “undoes rheumatism”.
In the first century AD, Roman natural philosopher Pliny the Elder wrote that a decoction of cannabis root in water “relaxes contractions of the joints”.
It’s clear that cannabis has been used in the treatment of arthritis and related conditions for thousands of years.
Today, there’s an abundance of anecdotal evidence that medicinal cannabis helps relieve arthritis symptoms, particularly pain.
Survey data has found that arthritis patients who use medical cannabis find it to be highly effective.
A survey by the Arthritis Foundation in the United States, where medical cannabis is widely found that 79% of patients are using CBD, have used it in the past, or are considering using it.
Modern science is finding that medicinal cannabis may be of benefit to arthritis patients.
However, more robust clinical research is needed to understand the true potential of medicinal cannabis as a treatment for arthritis.
Arthritis and the Endocannabinoid System (ECS)
Preclinical studies have found evidence of a relationship between the Endocannabinoid System (ECS), pain and arthritis.
However, it’s not clear how this relationship works, or if it’s applicable to humans.
Endocannabinoid receptors have been found in the connective tissue, cartilage and bone of patients with osteoarthritis and rheumatoid arthritis.
This suggests a possible role of cannabinoids in regulating inflammation, and cartilage breakdown and bone remodelling processes that take place during the diseases.
Endocannabinoid receptors (CB1 and CB2) in immune cells may also modulate immune and inflammatory responses.
By acting on these receptors, the effects of medicinal cannabis may help to stop or slow down the progression of arthritis.
‘A significant analgesic effect’
The first-ever controlled trial of cannabis-based medicine in rheumatoid arthritis found that cannabis was an effective painkiller.
The 2005 study compared a cannabis-based oral mucosal spray (roughly 1:1 THC:CBD) with a placebo in 58 patients over five weeks of treatment.
Patients were treated in the evening and assessments were made each morning.
The study assessed pain on movement, pain at rest, morning stiffness and sleep quality using two measures — a questionnaire and disease activity score.
In comparison with placebo, the cannabis-based medicine produced statistically significant improvements in pain on movement, pain at rest, and quality of sleep.
There was no effect on morning stiffness, although baseline scores were low.
Any adverse effects were mild or moderate.
The authors said the results “represent benefits of clinical relevance” and show the need for more detailed investigation.
‘Therapeutic potential’ of topical CBD
A 2016 study found using CBD gel on rats with arthritis “significantly reduced joint swelling” as well as spontaneous pain, immune cell infiltration and thickening of the synovial membrane.
The authors concluded the transdermal administration of CBD has “long-lasting therapeutic effects without psychoactive side-effects”.
“Thus, use of topical CBD has potential as effective treatment of arthritic symptomatology.
“The data presented suggest transdermal CBD is a good candidate for developing improved therapies for these debilitating disease.”
A 2017 study found that injecting CBD into rats with osteoarthritis reduced joint inflammation and blocked pain. It also helped to prevent the later development of pain and nerve damage.
Clinical trials are needed to determine the effectiveness of CBD treatment in human arthritis patients.
A New Zealand review
In 2020, the New Zealand Medical Association published a review of the research on cannabis and arthritis.
The review included 19 preclinical and two clinical studies.
The authors said that the Endocannabinoid System may play a role in acute pain and inflammation in animals and humans “the full extent of its role in arthritis is unclear”.
They said Sativex may be somewhat effective for relieving some symptoms of rheumatoid arthritis, but there was a lack of evidence on the long-term effects of cannabis-based medicines.
A matter of time
There’s a clear gap between the anecdotal evidence in favour of using medicinal cannabis for arthritis and the scientific research.
Surveys suggest more than half of arthritis patients are already using medical cannabis and find it highly effective for relieving pain and morning stiffness, and improving physical movement and quality of sleep.
While there’s currently a lack of clinical research looking at cannabis and arthritis, it seems that patients aren’t waiting for the science to catch up.
Nevertheless, more high-quality clinical trials are essential for patients, caregivers and healthcare professionals to have confidence in using and prescribing cannabis-based medicines for arthritis.