Parkinson's disease and motor fluctuations: long-acting carbidopa/levodopa (CR-4-Sinemet).

Long-acting levodopa/carbidopa combination (CR-4-Sinemet) was compared with traditional levodopa/carbidopa (Sinemet) open label in 20 patients with Parkinson's disease and "wearing-off" phenomena. After 4 to 6 weeks of therapy with CR-4-Sinemet, the number of daily doses of medication dropped significantly compared with traditional Sinemet, disability improved, and "on" time increased. In nine patients receiving CR-4-Sinemet for 3 months, the number of daily doses and the on time without chorea remained significantly improved. CR-4-Sinemet peaked in plasma after 2 hours, and moderately high levels remained at 4 hours after the dose. Side effects were similar between traditional Sinemet and CR-4 Sinemet.