Tolcapone is a catechol-O-methyltransferase (COMT) inhibitor used as adjunct therapy in the symptomatic management of idiopathic Parkinson's disease. Tolcapone is a drug that inhibits the enzyme catechol-O-methyl transferase (COMT).
- Mechanism
- Curator reviewed
The precise mechanism of action of tolcapone is unknown, but it is believed to be related to its ability to inhibit COMT and alter the plasma pharmacokinetics of levodopa, resulting in an increase in plasma levodopa concentrations. The inhibition of COMT also causes a reduction in circulating 3-OMD as a result of decreased peripheral metabolism of levodopa. This may lead to an increase distribution of levodopa into the CNS through the reduction of its competitive substrate, 3-OMD, for transport mechanisms. Sustained levodopa concentrations presumably result in more consistent dopaminergic stimulation, resulting in greater reduction in the manifestations of parkinsonian syndrome.
- Primary indication
- Used as an adjunct to levodopa/carbidopa therapy for the symptomatic treatment of Parkinson's Disease.Curator reviewed · 1 structured indication
- Formula / weight
- C14H11NO5 · 273.2408 g/mol (avg)
- First approval
- Canada, 1997 · United States, 2004 · European Union, 2016
- Code names
- RO 40-7592
- Brand names
Resolves to
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Which drugs share a target with Tolcapone, and which of those have an active Phase 3 trial?
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