Dopamine agonists in the treatment of non-motor symptoms of Parkinson's disease: depression

Background: Psychiatric symptoms such as depression are common non-motor comorbidities of Parkinson's disease (PD). Depressive symptoms in patients with PD are a major complication that impairs quality of life independent of motor symptoms. The relationship between PD and comorbid depression is not completely understood. Methods and Results: Evidence suggests that both PD and depression may be mediated by degeneration of the dopaminergic system. Recent and ongoing research is exploring the potential role of dopamine agonists in the treatment of depressive symptoms in patients with PD. Conclusion: Experimental studies suggest a primary relationship and the importance of dopaminergic mechanisms in PD and depression. Patients with PD and depression might benefit from a global approach. Thus, treatment with dopamine agonists promises to reduce motor complications as well as depressive symptoms, avoiding multiple drug interactions as well as possible antidepressant medication side effects.