Six-year results of treatment with levodopa plus benzerazide in Parkinson's disease.

A combination of levodopa and a peripheral dopa-decarboxylase inhibitor, benzerazide (Ro 4-4602), was studied over a 75-month period of observation in 132 patients with Parkinson's disease. The combined therapeutic approach was without biological toxicity, was well tolerated by 95 percent of patients, and was highly effective: 72 percent of patients improved by more than 50 percent on a functional activity scale and the group as a whole improved on an objective battery by a mean of 46 percent. Neurologic side effects of abnormal involuntary movements, falls, and oscillations in performance were not improved over levodopa used alone. The combined therapy is to be preferred over the use of levodopa alone in the symptomatic management of Parkinson's disease.