Motor fluctuations often complicate chronic levodopa treatment of Parkinson's disease. Pharmacologically, these phenomena are characterized by a progressive shortening of the duration of action of levodopa and a gradual narrowing of the range of 'optimally effective' doses, able to improve parkinsonian akinesia without including abnormal involuntary movements. The effects of a continuous intravenous infusion of levodopa lasting 9 ± 0.3 days on these clinical-pharmacological indices have been studied in 12 parkinsonian patients. Continuous infusion therapy gradually ameliorated motor fluctuations by more than 40%, and this improvement lasted for at least 6 days after resuming standard oral therapy. Moreover, levodopa duration of action was prolonged by about 30%, and the range of 'optimally effective' dose was widened by about 50%. The above data suggest the possibility of plastic modifications of the pathogenetic mechanisms underlying motor fluctuations in Parkinson's disease, and a potential deleterious effect of intermittent oral therapy. Consequently, continuous dopaminergic stimulation, when used in the early stages of the disease, might theoretically have a prophylactic role on the development or worsening of motor fluctuations.
|Translated title of the contribution||Changes in the nigrostriatal dopaminergic receptor system following continuous dopaminergic infusion in Parkinson's disease|
|Number of pages||5|
|Journal||Rivista di Neurologia|
|Publication status||Published - 1991|
ASJC Scopus subject areas
- Clinical Neurology