Levodopa in the treatment of Parkinson's disease: myths and realties

In recent years we have witnessed a growing tendency to opt for the use of dopamine agonists (DA) as treatment for Parkinson's disease (PD), with the aim of delaying as far as possible the development of fluctuations and dyskinesias. Yet, levodopa continues to be the most effective antiparkinson drug and is probably the one that improves the greatest number of symptoms of the disease. This article reports on the results of a comprehensive review of the literature dealing with the benefits and risks of levodopa treatment in patients with PD which was conducted by a group of expert neurologists and members of the Spanish Neurology Society's Movement Disorder Group. The main conclusion reached in this article is that levodopa continues to be the most effective treatment for PD. Although the risk and incidence of developing dyskinesias remains at a lower level in the group initially treated with DA, the number of patients who develop disabling dyskinesias is very low in all the studies and is similar for DA and for levodopa. Scores on the quality of life scales are also similar in the two groups, which casts some doubt on the impact that these motor complications have on the quality of life of patients with PD. In view of these findings, we should consider whether there is any real justification for depriving patients of the good control of their symptoms offered by levodopa owing to the fear of developing dyskinesias or mild motor fluctuations that are not really going to have any negative effect on their quality of life. There is also the possibility of their developing severe side effects, which are more frequent with the use of DA.