Levodopa in plasma correlates with body weight of parkinsonian patients

Abstract

Background: Antiparkinsonian comedication and/or altered gastrointestinal motility and absorption influence plasma levels of levodopa. Another putative factor may represent body weight. The objective of our study was to examine the relationship between body weight and levodopa in plasma of parkinsonian patients.Methods: We enrolled 26 individuals into this trial on the resorption of levodopa. A standardized protocol was used, which eliminated influencing factors, such as comedication, activity, food and estimated levodopa plasma levels at fixed timepoints.Results: Levodopa amount (Spearman R=-0.48; p=0.013) and maximum concentration (Spearman R=-0.50; p=0.008) in plasma correlated negatively with body weight.Conclusion: Doses of levodopa should be considered in relation to body weight. Thus severe loss of weight may reduce the need for oral levodopa intake by parkinsonian subjects and may represent a putative factor in the occurrence of dyskineasia in these patients unless there is a concomitant reduction in the dose of oral levodopa.