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Rationale for Use of Dopamine Agonists in Parkinson's Disease: Review of Ergot Derivatives

Published online by Cambridge University Press:  02 December 2014

Pierre J. Blanchet*
Affiliation:
Faculty of Dentistry, Université de Montréal and CHUM/Campus St. Luc, Montréal (Québec), Canada
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Abstract

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While dopamine agonists are still traditionally used as adjunct medications to improve performance and smooth out motor response complications in advanced levodopa-treated Parkinson's disease, they are increasingly used in monotherapy or early in combination with levodopa particularly in patients under 65 years of age. Long-term studies using bromocriptine showed efficacy in lowering the cumulative levodopa dose and reducing the early incidence of levodopa-related motor response complications. New dopamine agonists have recently shown efficacy as adjunct medications in short-term trials. While we now have more options to fit our individual patients' needs and tolerance, it is important to view the new agonists in the light of the results obtained with ergot derivatives. In this article, the rationale for use and efficacy profile of the ergolines are briefly reviewed.

Résumé

RÉSUMÉ

Les agonistes dopaminergiques sont traditionnellement utilisés comme adjuvants dans le but d'améliorer la performance et réduire les fluctuations motrices observées chez les malades dopa-traités aux stades avancés de la maladie de Parkinson. Toutefois, ils sont de plus en plus prescrits précocément dans la maladie, en monothérapie ou en combinaison avec la L-DOPA, surtout chez les malades de moins de 65 ans. Les essais clin-iques prolongés avec la bromocriptine ont bien montré son efficacité à réduire la dose cumulative de L-DOPA util-isée et à diminuer l'incidence précoce des complications motrices associées à la dopathérapie. De nouveaux agonistes non dérivés de l'ergot de seigle ont récemment démontré leur efficacité lors d'essais cliniques de courte durée, nous donnant davantage de choix pour maîtriser les signes et symptômes de la maladie et les problèmes d'intolérance pré-coce. Il apparaît opportun de revoir les indications du traitement agoniste et les effets des dérivés de l'ergot de sei-gle dans la maladie de Parkinson en attendant la publication d'études cliniques contrôlées comparant les nouveaux agonistes aux premiers mis sur le marché.

Type
Research Article
Copyright
Copyright © The Canadian Journal of Neurological 1999

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