Tolcapone
Tolcapone (Tasmar)
Tolcapone
( TOHL-kah-pohn)
Pregnancy Category: C Tasmar (Rx)

Classification: Antiparkinson drug

Action/Kinetics: Reversible inhibitor of catechol-O-methyltransferase (COMT), resulting in an increase in plasma levodopa. When given with levodopa/carbidopa, plasma levels of levodopa are more sustained, allowing for more constant dopaminergic stimulation of the brain. May also increase side effects of levodopa. Rapidly absorbed from the GI tract; peak levels: 2 hr. Food given within 1 hr before or 2 hr after PO use decreases bioavailability by 10%-20%. Over 99.9% bound to plasma protein. t 1/2, elimination: 2-3 hr. Almost completely metabolized in the liver; excreted in the urine (60%) and feces (40%).

Uses: Adjunct to levodopa and carbidopa for the treatment of idiopathic Parkinson's disease. Reserved for clients taking levodopa-carbidopa who have symptom fluctuations and are not responding to or candidates for other therapies.

Contraindications: Use with a nonselective MAO inhibitor. In clients with liver disease, history of nontraumatic rhabdomyolysis or hyperpyrexia, confusion possibly related to the drug, and in those withdrawn from tolocapone due to hepatocellular injury.

Special Concerns: Use with caution in severe renal or hepatic impairment and during lactation.

Side Effects: GI: N&V;, anorexia, diarrhea, constipation, xerostomia, abdominal pain, dyspepsia, flatulence, acute fulminant liver failure. CNS: Hallucinations, dyskinesias, sleep disorder, dystonia, excessive dreaming, somnolence, confusion, dizziness, headache, syncope, loss of balance, hyperkinesia, paresthesia, hypokinesia, agitation, irritability, mental deficiency, hyperactivity, panic reaction, euphoria, hypertonia. CV: Orthostatic hypotension, chest pain, hypotension, chest discomfort. Respiratory: URTI, dyspnea, sinus congestion. Musculoskeletal: Muscle cramps, stiffness, arthritis, neck pain. GU: Hematuria, UTIs, urine discoloration, micturition disorder, uterine tumor. Dermatologic: Increased sweating, dermal bleeding, skin tumor, alopecia. Ophthalmic: Cataract, eye inflammation. Body as a whole: Falling, fatigue, influenza, burning, malaise, fever, rhabdomyolysis.
NOTE: Clients over 75 years of age may develop more hallucinations but less dystonia. Females may develop somnolence more frequently than males.

Laboratory Test Alterations: AST, ALT.

Overdose Management: Symptoms: Nausea, vomiting, dizziness, possibility of respiratory difficulties. Treatment: Hospitalization is advised. Give supportive care.

How Supplied: Tablets: 100 mg, 200 mg

Dosage
?Tablets Adjunct for Parkinsonism.
Initial: 100 t.i.d. with or without food. Use 200 mg t.i.d. only if anticiapted benefit is justified. Do not increase the dose to 200 mg t.i.d. in those with moderate to severe liver cirrhosis.