Pharmacotherapy of fibromyalgia – current knowledge

Fibromyalgia is a chronic pain syndrome, which affects 2–4% of the general population. Despite its substantial prevalence in the community, the underlying pathophysiology of fibromyalgia remains largely unknown, and the diagnosis is made using symptom-based criteria. As a result, patients may be classified as suffering from fibromyalgia in spite of differing in the pathogenesis of their complaints. Therefore it is no surprise, that the efficacy of pharmacotherapy of fibromyalgia remains limited. This work aims to provide a summary of current knowledge based on trials which assessed the efficacy of fibromyalgia pharmacotherapy. The drugs with the highest amount of research proving their efficacy in reducing fibromyalgia symptoms are duloxetine, milnacipran, pregabalin and amitriptyline. Studies documenting the efficacy of venlafaxine, gabapentin and antidepressants other than serotonin and noradrenalin reuptake inhibitors are smaller in number. Data obtained in trials verifying the effects of selective serotonin reuptake inhibitors, tramadol or cannabinoids are too sparse to draw any clear conclusions. There are reports indicating that opioids (other than tramadol) are contradicted in fibromyalgia, the use of selective serotonin reuptake inhibitors seems disputable too, due to the risk of inducing a change in the pain phenotype. There is a lack of data suggesting the efficacy of nonsteroid anti-inflammatory drugs in fibromyalgia. Furthermore, there are individual studies showing beneficial effects of other drugs and dietary supplements or combinations thereof in patients with fibromyalgia. In summary, the obtained data show that the amount of medicines whose efficacy in fibromyalgia has been verified in numerous studies is limited. More studies exploring the pathophysiology of fibromyalgia and trials verifying the effects of pharmacotherapy are needed to achieve the optimal efficacy of fibromyalgia pharmacotherapy.