Entacapone is an inhibitor of catechol-O-methyltransferase (COMT). It is used in combination with levodopa and carbidopa (Sinemet) to treat the end-of-dose 'wearing-off' symptoms of Parkinson's disease. Entacapone helps the levodopa and carbidopa work better by allowing more of it to reach the brain, where it has its effects.
