The clinical course and the side effects of high-level levodopa therapy over a six-year period were studied in 80 severely akinetic parkinsonian patients treated for the first time before June 1968. Levodopa improved the quality of life in greater than 53% of patients, but failed to modify the progression of the disease or change the prognosis. Seventeen "idiopathic Parkinson" patients died after a duration of illness of 9.5 years. Despite the drawbacks, levodopa is still the best available treatment for akinetic parkinsonism.