Amantadine in Parkinson's disease: pro and contra.

After almost 30 years amantadines have reached a definite position in the therapy of Parkinson's disease. Especially in akinetic crisis and in combination with L-Dops amantadine improves the major symptoms of parkinsonism if L-Dopa alone is no more sufficient. Also in cases where L-Dopa treatment is not effective there is reported of a positive reaction on amantadine (Sandyk, 1987). Another advantage is their low side effects and their fast effectiveness. A monotherapy with amantadine is indicated in the early phase of Parkinson's disease and in cases of slight symptoms. According to Kornhuber and Streifler (1992) two thirds of parkinsonian patients react by such a monotherapy with a global improvement of 20 to 40%. After a long-term treatment amantadines are also still effective. In the beginning of the 1970ies opponent statements were made but now a days no larger amantadine study could show a definite decline in initial response to these drugs. Long-term studies with a larger population of patients indicate effects for many years. With additional knowledge about the pathogenesis of Parkinson's disease and about the role of the neurotoxicity though glutamate amantadines as NMDA-receptor antagonists become a great importance as neuroprotective substances.