Fibromyalgia is one of the most common chronic pain syndromes. It is characterized by diffuse musculoskeletal pain, in addition to extreme fatigue and mood and sleep disturbances. The pathogenesis of fibromyalgia is not clear. It usually affects women more than men and has a genetic preponderance. Its prevalence in the general population is estimated to be approximately 7%, and it is more common among women than men.
Fibromyalgia can have tremendous physical, as well as psychological, impacts on patients. For example, many patients may be unable to accomplish various tasks at work and home, resulting in physical disability, which can be accompanied by anxiety and depression. Unfortunately, in most patients, fibromyalgia is chronic, and the main treatment is pain control medications. These medications include simple analgesics, pregabalin, and opiates. Patients with fibromyalgia may also benefit from tricyclic antidepressants, benzodiazepines, and other types of antidepressants. However, many of these medications are associated with adverse effects, which affect compliance. As a result, many patients with fibromyalgia experience continuous pain.
There are only a few studies in the literature on the use of cannabis by fibromyalgia patients. In these studies, the patients used unlicensed cannabis from different suppliers, and the studies contained no information on either the type or amount (in grams) of cannabis used. In general, the patients in these studies reported favorable effects of cannabis use. A systematic review of the use of synthetic cannabinoids in fibromyalgia (nabilone, 2 studies) found evidence (very low quality) of a greater reduction in pain and limitations in health-related quality of life in the synthetic cannabinoid group as compared with a placebo group in one study and better effects of synthetic cannabinoids on sleep than amitriptyline in another study. The aim of the present study was to examine the effects of licensed MC on patients with fibromyalgia in an Israeli population.
The main finding of the present study was that MC treatment was associated with significant favorable outcomes in every item evaluated in the FIQR. In some cases, the improvement was so marked that the patients completely ceased treatments they had taken previously. In other cases, the patients significantly reduced the dose or type of medication they had taken prior to MC treatment.
For some items of the FIQR, all the patients reported a favorable outcome. These included the effect of MC on pain and energy levels. For other items, the impact was less prominent, yet significant. These included the impact of MC on memory problems and daily activities of living, such as household activities (e.g., cleaning the house and changing bed sheets) and shopping (e.g., carrying grocery bags).
Another major benefit of MC treatment was a lack of serious adverse effects. The patients reported a few mild adverse effects, including dry mouth, redness of the eyes, and feeling hungry. These adverse effects appeared from the start of the treatment. The first 2 adverse effects were usually transient, lasting only a few weeks, and were mainly encountered in cases where the mode of MC was smoking. Many patients adapted to feeling hungry by eating prior to the use of MC.