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    DEA Class;  Rx

    Common Brand Names; Tasmar

    • Antiparkinson Agents, COMT Inhibitors

    Peripheral and centrally acting oral COMT inhibitor; improves levodopa availability in the CNS; more potent than entacapone
    Used for adults with Parkinson’s disease as an adjunct to levodopa/carbidopa
    Less favorable side effect profile vs. entacapone; boxed warning exists in labeling for hepatotoxicity and risk for hepatocellular injury and liver failure

    Indicated for use as adjunctive treatment to levodopa and carbidopa for the treatment of signs and symptoms of idiopathic Parkinson’s disease.


    Liver disease or history of tolcapone-induced hepatotoxicity

    History of: non-traumatic rhabdomyolysis, drug-related hyperpyrexia & confusion

    • Dyskinesia (45-50%)
    • Nausea (30-35%)
    • Insomnia (21-25%)
    • Hallucinations (8-24%)
    • Excessive dreaming (16-21%)
    • Diarrhea (16-20%)
    • Anorexia (16-20%)
    • Dystonia (16-20%)
    • Muscle cramping (16-20%)
    • Somnolence (16-20%)
    • Orthostatic hypotension (11-15%)
    • Confusion (10-11%)
    • Headache (10-11%)
    • Vomiting (8-10%)
    • Constipation (6-8%)
    • URI (5-7%)
    • Fatigue (3-7%)
    • Abdominal pain (5-6%)
    • Xerostomia (5-6%)
    • UTI (5%)
    • Hematuria (4-5%)
    • Syncope (4-5%)
    • Dyspnea (3%)
    • Loss of balance (2-3%)
    • Urine discoloration (2-3%)
    • Chest pain (1-3%)
    • Hyper/hypokinesia (1-3%)
    • Parasthesia (1-3%)
    • Transaminases increased (1-3%, usually 3x ULN in first 6 mos of therapy)
    • Hypotension (2%)
    • Neck pain (2%)
    • Stiffness (2%)
    • Sinus congestion (1-2%)

    Risk of potentially fatal hepatotoxicity; withdraw drug if no improvement in 3 wk

    Do not initiate treatment if AST/ALT >ULN; discontinue if liver enzymes >2 xULN

    Impulse control/compulsive behaviors: Risk of uncontrollable sexual, gambling or other urges

    Orthostatic hypotension, diarrhea, hallucinations, psychotic-like behavior, rhabdomyolysis, renal/hepatic impairment, hematuria, hyperpyrexia, confusion, and fibrotic complications may occur

    May be linked to higher melanoma risk in Parkinson’s patients

    Avoid abrupt withdrawal

    May increase risk for falling asleep during activities of daily living

    Do not coadminister with nonselective MAO inhibitor (ie, MAO-A inhibitors); combination may result in result in inhibition of the majority of the pathways responsible for normal catecholamine metabolism

    Discontinued in Canada

    Pregnancy Category: C

    Lactation: not known if secreted in breast milk, use caution


    600 mg/day PO.


    600 mg/day PO.


    Safety and efficacy have not been established. 


    Safety and efficacy have not been established. 


    Not indicated.



    • 100mg