Levodopa is a central nervous system agent that helps people with Parkinson’s because it is converted into dopamine in the brain. It helps to alleviate the symptoms of the disease by providing a supply of dopamine, which is lacking in people with Parkinson's.
Levodopa works best to help treat the slowness and stiffness or rigidity associated with Parkinson’s disease, and in some cases may treat the tremor as well. It does not slow or reduce the progression of Parkinson’s disease.