LEVODOPA IN PARKINSON'S DISEASE—AUSTRALIAN COLLABORATIVE TRIAL

Abstract

Nineteen neurologists in four Australian States collaborated in this trial of the therapeutic effects and adverse side reactions of levodopa in Parkinson's disease. The trial comprised 216 patients who took levodopa for periods varying from 5 to 15 months. Clinical observations, recorded on a standard protocol and repeated at regular intervals, listed the degree of severity of 12 specific disabilities of Parkinson's syndrome, the patient's intellect and mood, and the effect of his disease on the activities of daily living and working capacity. Total disability scores were calculated from a rating scale. At the final evaluation, overall improvement in condition was observed in 88% of patients (34% marked, 36% moderate, 18% slight). The duration of Parkinson's disease had no influence on the result of treatment with levodopa; increasing age had a slightly adverse effect, while patients who had a previous thalamotomy seemed to fare better. Adverse side effects to the drug are listed in detail. Nausea and vomiting could often be prevented by gradual increments in dosage, whereas drug‐induced involuntary movements occurred in 51% of cases and usually demanded a dose reduction. No significant changes in the patients' electroencephalograms and electrocardiograms were found, and exhaustive, repeated laboratory tests failed to show any adverse toxic effects on the bone marrow, liver or kidney.