The Effect of Duloxetine on Primary Pain Symptoms in Parkinson Disease

To study the effect of duloxetine (Cymbalta), a selective serotonin and norepinephrine reuptake inhibitor, on pain symptoms in Parkinson Disease (PD).Twenty-three patients with PD with painful phenomena were treated with duloxetine for 6 weeks in an open-label design. Assessments were performed before and at treatment completion and consisted of a Visual Analogue Scale, the Brief Pain Inventory, Short-Form McGill Pain Questionnaire, Parkinson Disease Quality of Life Questionnaire-39-item version, and motor part of the Unified Parkinson Disease Rating Scale. Pain threshold was assessed by quantitative sensory tests.Thirteen of the 20 patients who completed the study reported varying degrees of pain relief. The mean Visual Analogue Scale, Brief Pain Inventory, and Short-Form McGill Pain Questionnaire scores decreased significantly. There was no change in pain threshold after treatment.Duloxetine seems to be effective for the treatment of central pain in PD.