Dilemma in the treatment of Parkinson's disease with L-dopa

L-Dopa pioneered the symptomatic therapy of Parkinson's disease. While this treatment proved effective in the treatment of parkinsonian akinesia, rigidity and tremor, prolonged L-dopa treatment was often noted to result in dyskinesia, psychosis and 'on-off' phenomena. This increasing disability of L-Dopa-treated parkinsonian patients, however, is not correlated with the duration of L-dopa treatment. Mortality due to Parkinson's disease has decreased significantly after the introduction of L-dopa treatment. The development of D1-selective dopamine agonists and the introduction of neuroprotective rather than symptomatic therapy are required for treating Parkinson's disease.