Research links cannabis to improvements in Fibromyalgia symptoms

The findings of a new study, using data collected from the UK, suggest treatment with cannabis is associated with an improvement in symptoms among fibromyalgia patients. 

Researchers examined data taken from over 300 fibromyalgia patients enrolled in the UK Medical Cannabis Registry, which is run by Sapphire Medical Clinics. 

After starting treatment with medicinal cannabis, patients reported improvements in fibromyalgia-specific symptoms, as well as overall health and quality of life. A statistically significant reduction in opioid use was also identified. 

Fibromyalgia is a complex, chronic condition, which can cause widespread musculoskeletal pain as well as other symptoms including muscle stiffness, brain fog, problems sleeping and low mood. It currently affects around one in 20 people and is more common in women than men.

There are limited treatment options, with doctors often relying on prescription drugs such as opioids and antidepressants to manage the symptoms. 

Previous studies have suggested that large numbers of fibromyalgia patients may be self-medicating with cannabis – and finding it helpful. One paper from 2021 found that around 60% of participants with fibromyalgia had tried CBD at some point. 

‘Statistically significant’ improvements in fibromyalgia symptoms and reduction in opioids

Researchers looked at data from 306 patients with a diagnosis of fibromyalgia who were prescribed cannabis at Sapphire Clinics. The majority of patients were female (70%) with an average age of 45-years-old. 

Just under half of the participants were already consuming cannabis, 38% were cannabis naive and 41 had used cannabis in the past. Patients were prescribed a variety of oil and flower products with an average daily dose of 100mg THC and 20mg of CBD.

The researchers used a number of standardised questionnaires to measure outcomes including fibromyalgia symptoms, sleep, anxiety, pain and health-related quality of life. They also looked at opioid consumption and adverse events. 

Patients reported improvements in health-related quality of life at one, three, six and 12 months. Statistically significant improvements were also observed in fibromyalgia-specific symptoms, pain, sleep and anxiety.

Just under a quarter (24%) of patients reported adverse events, with the majority being either mild or moderate, and none of which were ‘life-threatening or disabling’. However, the researchers note that this is slightly higher than has been reported in the overall population of the registry.

The findings also suggest a link between cannabis treatment and a reduction on opioid use, with a ‘statistically significant’ reduction in the average oral morphine dose at three months compared to baseline.

While this study is unable to infer any ‘clinical significance’ due to its design, previous research has also reported a reduction in opioid use of up to 78% in patients prescribed cannabis.

Call for further research into cannabis and fibromyalgia

Real-world evidence plays an important role in collecting the outcomes and experiences of cannabis patients. However, the authors note a number of limitations which should be taken into account, namely the lack of a control or comparison group in the study which means ‘causality cannot be concluded’ and biases can’t be excluded. 

They are now recommending further research, including randomised control trials (RCTs), be carried out to examine the findings more closely. 

The authors conclude: “The results of this study suggest that there is an associated improvement in fibromyalgia-specific symptoms, in addition to sleep, anxiety, and health-related quality of life. Those who reported prior cannabis use appeared to have a greater response to treatment effects. 

“In addition, non clinically significant reductions in opioid prescribing were observed. CBMPs [cannabis-based medicinal products] were largely well-tolerated; however, the adverse event incidence in fibromyalgia was higher than other conditions captured within the UKMCR.”

They add: “Despite these results, the notable limitations of the study design mean that causation cannot be proven in this study. Instead, randomised controlled trials are still necessary to examine this effect in earnest. However, this study adds to the clinical evidence that can inform the design of such trials, as well as current clinical practice.”