Pharmacotherapy options for complex regional pain syndrome.

Complex regional pain syndrome is a painful disorder of unclear etiology, typically involving the distal part of one limb, represented by spontaneous and evoked pain as well as autonomic, motor and trophic abnormalities. It can be incapacitating and severely affect function and quality of life. Although full-blown complex regional pain syndrome can be diagnosed easily, less fulminate forms of the syndrome often remain undiagnosed. Controlled trials have demonstrated that a short course of oral corticosteroids, intranasal or intramuscular calcitonin, intravenous bisphosphonates, free-radical scavengers, gabapentin, regional intravenous sympathetic blocks with bretylium and spinal cord stimulation or physical therapy and occupational therapy can be efficacious for complex regional pain syndrome. Nonetheless, the management of this syndrome is difficult because currently available drugs and technologies do not provide adequate pain relief for a considerable percentage of sufferers. The present review focuses primarily on the pharmacotherapy of complex regional pain syndrome and describes briefly the epidemiology, pathogenesis and clinical manifestations of the syndrome.