In 1993, a study was undertaken at the Hand Clinics of Loyola University Medical Center in Chicago to investigate the role of the neuropeptides in the pathogenesis of Reflex Sympathetic Dystrophy. All of the patients had recurrent or continuous pain, swelling, and stiffness of one or both extremities following either acute trauma or surgical intervention. All of the patients showed a markedly increased level of bradykinin as well as calcitonin gene-related peptide. The levels of bradykinin were four times as high as the controls. A few showed increased levels of the other neuropeptides. With these results, we agree with Veldman, Goris and others who consider Reflex Sympathetic Dystrophy to be an exaggerated regional inflammatory disorder.