Tolcapone

Tolcapone

File:Tolcapone.png
File:Tolcapone3d.png
Clinical data
Pregnancy category	US: C (Risk not ruled out)
Routes of administration	Oral
ATC code	N04BX01 (WHO)
Legal status
Legal status	US: ℞-only
Pharmacokinetic data
Bioavailability	65%
Protein binding	>99.9%
Elimination half-life	2-3.5 hours
Identifiers
IUPAC name 2-dihydroxyamino-4- (4-methylbenzoyl)- cyclohexa-2,4-diene-1,6-dione
CAS Number	134308-13-7
PubChem CID	4659569
DrugBank	APRD00445
E number	{{#property:P628}}
ECHA InfoCard	{{#property:P2566}}
Chemical and physical data
Formula	C14H11NO5
Molar mass	273.241 g/mol

Tolcapone is a drug that inhibits the enzyme catechol-O-methyl transferase (COMT). It is used in the treatment of Parkinson's disease as an adjunct to levodopa/carbidopa medication. It is a yellow, odorless, non-hygroscopic, crystalline compound with a relative molecular mass of 273.25. The chemical name of tolcapone is 3,4-dihydroxy-4’-methyl-5-nitrobenzophenone. Its empirical formula is C₁₄H₁₁NO₅.

Tolcapone has the ability to cross the blood-brain barrier and thus exerts its COMT inhibitory effects in the CNS as well as in the periphery.

Tolcapone has demonstrated significant hepatotoxicity that limits the drug's therapeutic utility to a drug of last resort. Entacapone, another COMT inhibitor, is a more popular selection for L-DOPA adjunct therapy in the treatment of Parkinson's Disease because it has a better side effect and toxicity profile.

Normally, administration of levodopa is compromised when COMT converts it to methyldopa. By preventing this effect, more of the levodopa that is administered reaches the CNS. Additionally, levodopa that is in the CNS, after being converted to dopamine, will not be degraded by COMT when tolcapone inhibits COMT activity. Template:Pharma-stub Template:Dopaminergic agents Template:WikiDoc Sources