Tremor in Parkinson disease: acute response to oral levodopa.

A single blind placebo-controlled study has been performed in order to investigate objectively the acute tremorolytic effect of oral L-Dopa in ten parkinsonians chronically treated with L-Dopa. Finger tremor was assessed by means of a computerized accelerometer method, at rest and during maintenance of a fixed posture. Both resting and postural tremor were significantly influenced by L-Dopa. An "acute test" with oral L-Dopa, especially when different tremor components are investigated, may be useful for identifying objectively parkinsonians whose tremor does not respond to drug therapy or shows a deterioration of drug-responsiveness.