Initial therapy for Parkinson's disease: levodopa vs. dopamine receptor agonists.J Neurol. 2002 Sep; 249 Suppl 2:II25-9.JN
Levodopa therapy is essential for patients in the advanced stages of Parkinson's disease. However, at early stages, DA agonist therapy has similar efficacy in the treatment of parkinsonism and a lower incidence of motor complications compared to levodopa therapy several years after the initiation of the therapy. The main factors causing motor complications have been speculated to be a severe reduction of dopaminergic nerve terminals because of disease progression, and a pulsatile stimulation of DA receptors using a drug with a short plasma half-life. DA agonists have longer plasma half-lifes than levodopa; therefore, they are expected to have a favorable effect on motor complications. Moreover, two clinical reports confirmed the potential neuroprotection by DA agonists. Although the patient's conditions should be considered in the selsction of a drug, DA agonist therapy is recommended as the initial therapy for Parkinson's disease.