Fibromyalgia and Cannabis (marijuana)
Fibromyalgia, a pain disorder which is widely considered to be neuropsychiatric in nature, is treated with cannabis in approximately 10% of patients in the USA (either through self-medication or prescription), and has been shown to respond favourably to the synthetic THC-mimic nabilone. In a study which documented the effect of nabilone on fibromyalgia sufferers, subjects experienced significant improvement of symptoms when administered the cannabinoid. Another study demonstrated that quality of life was markedly improved in fibromyalgia sufferers that self-administered oral or smoked cannabis.
Serotonin levels in the platelets are also known to be affected in fibromyalgia, although it is thought that deficiency of serotonin, rather than over-abundance, is responsible for the sufferer’s aberrant perception of pain. This disparity is not fully understood, and is somewhat surprising given the high degree of comorbidity between the diseases: in one study, up to 63% of primary fibromyalgia sufferers also reported symptoms of migraine, in another, 22.2% of primary migraine sufferers were also found to have fibromyalgia. This disparity may be partly explained by gender differences, as none of the male migraine sufferers reported symptoms of fibromyalgia, and the latter disease is overwhelmingly experienced by women, who comprise 90% of sufferers.