What is the best initial treatment of Parkinson's disease?

No studies clearly demonstrate the best initial treatment for Parkinson's disease. Levodopa improves motor function in Parkinson's disease; however, long-term use is associated with irreversible dyskinesias and motor fluctuations. Compared with placebo, selegiline improves the motor symptoms of Parkinson's disease and allows a physician to delay the introduction of levodopa by 9 to 12 months (strength of recommendation [SOR]: A, based on randomized controlled trials). Dopamine agonists--alone or combined with levodopa--have fewer associated dyskinesias and other motor complications but produce lower scores on activities of daily living and Unified Parkinson's Disease Rating Scale (UPDRS) when compared with levodopa alone (SOR: A, based on systematic reviews of randomized controlled trials). Drug choices should be based on each patient's individual symptoms and response to medication