The Clinical Picture and Plasma Levodopa Metabolite Profile of Parkinsonian Nonresponders
- 1 April 1977
- journal article
- research article
- Published by American Medical Association (AMA) in Archives of Neurology
- Vol. 34 (4), 228-232
- https://doi.org/10.1001/archneur.1977.00500160042007
Abstract
• Three parkinsonian patients who were nonresponders to levodopa treatment did not improve when shifted to levodopa-decarboxylase inhibitor combination but, instead, experienced involumtary movements. Their plasma levodopa and metabolite profiles showed unusually high baseline 3-0-methyldopa concentrations that further increased significantly during the decarboxylase inhibitor regimen. All patients had 3-0-methyldopa to levodopa ratios greater than 1, even two hours after therapy. Patients who are responders to levodopa-decarboxylase inhibitor combination or to levodopa alone had 3-0-methyldopa to levodopa ratios of less than 1. We discuss the role of 3-0-methyldopa as a metabolite and the significance of the 3-0-methyldopa to levodopa ratio as a predictor of patients' response to levodopa.This publication has 8 references indexed in Scilit:
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