[Dopaminergic treatment and parkinsonian syndromes].

Chronic dopamine treatment usually provides partial and temporary improvement of extrapyramidal signs in about 40p.cent of the patients with multiple system atrophy. Exceptionally, dopamine agonists may provide a significant and persistent improvement in progressive supranuclear palsy. For patients with Lewy body dementia, levodopa often provides a significant improvement of the extrapyramidal syndrome in about 70p.cent of the treated patients. Dopamine treatment generally has no effect on secondary extrapyramidal syndromes caused by vascular parkinsonism or neuroleptics. Antiparkinsonian treatment can cause several complications, particularly degenerative parkinsonian syndromes with an increased frequency of cognitive disorders and dysautonomia. Consequently, antiparkinsonian agents should only be proposed within the framework of a differential diagnosis between parkinsonism and idiopathic Parkinson's disease then continued only if the risk/benefit ratio, systematically evaluated for each patient, is favorable.