Initial Therapy for a 67-year-old woman with Newly Diagnosed Parkinson's disease?

What should be initial therapy for a 67-year-old woman with newly diagnosed Parkinson's disease?
A. Levodopa/carbidopa combination
B. Dopamine agonist
C. Levodopa/carbidopa plus a COMT inhibitor
D. MAO-B inhibitor
E. Any of the above choices

Answer:  E. Any of the above choices

Discussion: 

Historically, Parkinson's disease has been treated with levodopa or carbidopa as a first-line agent. Levodopa is very effective and almost all patients will respond to treatment. Carbidopa, a decarboxylase inhibitor, reduces nausea and vomiting by preventing peripheral conversion of levodopa to dopamine and allowing more levodopa to act centrally. Evidence suggests that individuals initially started on levodopa tend to develop dyskinesias earlier than those started on dopamine agonists. Many clinicians have now started using dopamine agonists as first-line treatment. However, this is not universally followed. Factors such as age, coexisting cognitive impairment, need for rapid response, and cost all can influence agent choice. Younger patients are at higher risk of developing lifetime motor complications, so a dopamine agonist is preferable; however, older individuals are less likely to develop levodopa-related complications. Since dopamine agonists tend to cause more psychiatric complications, levodopa is preferred in cognitively impaired patients. Levodopa is also preferred when rapidity of onset is desired and when cost is a factor. Adding a COMT inhibitor to levodopa may reduce motor complications and is another early treatment strategy; however, this approach raises costs significantly. MAO-B inhibitors, such as selegiline, may be useful for mild disease.