Exogenous levodopa is not toxic to elderly subjects with non-parkinsonian movement disorders: further clinical evidence.

We report three women between 80 and 87 years of age who had longstanding essential tremor. Due to an erroneous diagnosis of Parkinsonism they had received levodopa preparations for 13, 16 and 25 years, respectively, with cumulative levodopa equivalent doses of 18.0, 9.0, and 4.1 kg. The patients showed neither dyskinesias nor signs of Parkinsonism. These observations do not support a detrimental role of chronic levodopa exposure in elderly individuals with essential tremor.