This study examines the effect of treatment of levodopa/entacapone on quality of life, as measured by the Parkinson's Disease-Questionnaire 8 (PDQ-8), in Parkinson's disease patients with no or minimal, non-disabling motor fluctuations.

This study examines the effect of treatment of levodopa/entacapone on quality of life, as measured by the Parkinson's Disease-Questionnaire 8 (PDQ-8), in Parkinson's disease patients with no or minimal, non-disabling motor fluctuations. Treatment with carbidopa/levodopa/entacapone will be compared with treatment with standard formulation levodopa/carbidopa.

Inclusion Criteria:

• Clinical diagnosis of idiopathic Parkinson's disease exhibiting at least 2 or 3 symptoms
• Motor functions must be regarded as non-disabling by the patient

Exclusion Criteria:

• History, signs or symptoms suggesting the diagnosis of atypical or secondary parkinsonism
• History of dyskinesia
• Previous or current use of entacapone or tolcapone
• Unstable Parkinson's disease patients requiring/receiving regimens of levodopa
• Subjects taking levodopa/DDCI controlled release or extended release formulations