Tolcapone in the management of Parkinson's disease.

Although levodopa remains the gold standard treatment for Parkinson's disease, many patients develop motor complications with chronic levodopa exposure. Tolcapone is a catechol-O-methyltransferase inhibitor that extends the action of levodopa. When used in conjunction with levodopa, tolcapone has been shown to be effective in improving motor fluctuations and reducing levodopa requirements in Parkinson's disease patients. However, rare reports of severe hepatotoxicity have limited its use. A recent review of the data on tolcapone-treated patients suggests that, with proper monitoring of liver function, the potential for hepatotoxicity with tolcapone use is negligibly small.