Metabolism and excretion of tolcapone, a novel inhibitor of catechol‐<i>O</i>‐methyltransferase

Abstract

Tolcapone is almost completely metabolized and excreted in urine and faeces (only 0.5% of tolcapone was excreted unchanged); glucuronidation is the most important route of metabolism. The relatively long duration of excretion is caused by the long half-life of 3-OMT.