Levodopa-Induced Dyskinesias

Abstract

The incidence of levodopa-induced dyskinesias in 20 Guamanian patients with parkinsonism-dementia (PD) was compared with that found in 14 Guamanians with amyotrophic lateral sclerosis (ALS), who were matched for dose and duration of drug exposure. While 55% of the PD patients developed abnormal involuntary movements during the first six months of treatment, none of the ALS patients manifested this complication. In PD patients no definite correlation could be documented between pretreatment parkinsonian severity or degree of response to levodopa and the appearance of dyskinesias. The results suggest that lesions of the type which produce Parkinson disease increase the susceptibility to levodopa-induced dyskinesias, but that apparently denervation supersensitivity alone does not account for this phenomenon.