Thirty-five patients with early mild Parkinson's disease were treated from the outset with small doses of L-dopa (mean dose, 396 to 454 mg daily) and a peripheral decarboxylase inhibitor, for a mean of 6 years. Overall mortality ratio was 1.2:1, worse for women than for men. After 6 years of treatment, only one-third of patients were better, and drug-related complications were common (peak-dose dyskinesias in 54% of patients, off-period dystonia 20%, wearing-off effects 52%, on-off oscillations 6%, visual hallucinations and toxic confusional states 17%). We found no evidence that long-term results were markedly improved with low-dose regimens.