Excessive daytime sleepiness and levodopa in Parkinson's disease: polygraphic, placebo-controlled monitoring.

The authors performed 72-hour polysomnography, including a levodopa-placebo-controlled choice reaction time test with continuous monitoring of cardiovascular variables in two patients with Parkinson's disease complaining of excessive daytime sleepiness on levodopa monotherapy. The subacute levodopa challenge was accompanied by physiologic sleep episodes, worsened reaction times, and a reduction in mean blood pressure and heart rate over baseline values, linked temporally to the sleep episodes.