Tolcapone

Trade names

• TASMAR

Actions

• Selective and reversible inhibitor of the enzyme catechol-O-methyltransferase (COMT).

Route of Administration

Oral

Bioavailability

65%

Plasma protein binding

>99.9%

Half-life

2-3 hours

Metabolism

Hepatic

Elimination

Renal 60%, biliary 40%

Important side-effects

Cases of fulminant liver failure have been reported. Before starting treatment with tolcapone, the physician should conduct appropriate tests to exclude the presence of liver disease. It is strongly advised to monitor patients for evidence of emergent liver injury after initiation of treatment.

Nausea.

Confusion, hallucinations, psychosis.

Dyskinesias.

Recommended dose

Start with 100 mg three times per day.

Given the risk of potentially severe hepatic injury, only under exceptional circumstanses is a dose increase to 200 mg three times daily motivated.

Renal impairment

No dose adjustment is necessary in atients with mild to moderate renal function impairment.

Caution is advised when treating patients with severe renal failure.

Hepatic impairment

Tolcapone is contraindicated in patients with evidence of hepatic dysfunction or elevated liver enzymes.