Drug Action
Tolcapone prevents the peripheral breakdown of levodopa, by inhibiting catechol- O- methyltransferase, allowing more levodopa to reach the brain.
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Drug reference
Tolcapone prevents the peripheral breakdown of levodopa, by inhibiting catechol- O- methyltransferase, allowing more levodopa to reach the brain.
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Adjunct to co-beneldopa or co-careldopa in Parkinson’s disease with ‘end-of-dose’ motor fluctuations if another inhibitor of peripheral catechol-O-methyltransferase inappropriate (under expert supervision) ▶BY MOUTH ▶Adult: 100 mg 3 times a day (max. per dose 200 mg 3 times a day) continuing beyond 3 weeks only if substantial improvement, leave 6 hours between each dose; first daily dose should be taken at the same time as levodopa with dopa-decarboxylase inhibitor, dose maximum only in exceptional circumstances
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Phaeochromocytoma. previous history of hyperthermia. previous history of neuroleptic malignant syndrome. previous history of rhabdomyolysis. severe dyskinesia
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Most patients receiving more than 600 mg levodopa daily require reduction of levodopa dose by about 30% CAUTIONS, FURTHER INFORMATION ▶Hepatotoxicity Potentially life-threatening hepatotoxicity including fulminant hepatitis reported rarely, usually in women and during the first 6 months, but late-onset liver injury also reported; discontinue if abnormal liver function tests or symptoms of liver disorder; do not re-introduce tolcapone once discontinued.
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→Appendix 1: tolcapone
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▶Common or very common Appetite decreased. chest pain. confusion. constipation. diarrhoea. dizziness. drowsiness . dry mouth. gastrointestinal discomfort. hallucination. headache. hyperhidrosis. influenza like illness. movement disorders. nausea. postural hypotension. sleep disorders. syncope. upper respiratory tract infection. urine discolouration. vomiting ▶Uncommon Hepatocellular injury ▶Rare or very rare Eating disorders. neuroleptic malignant syndrome (reported on dose reduction or withdrawal). pathological gambling. psychiatric disorders. sexual dysfunction
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Toxicity in animal studies—use only if potential benefit outweighs risk.
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Avoid—present in milk in animal studies.
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Manufacturer advises avoid.
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Caution if eGFR less than 30 mL/minute/1.73 m2.
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Test liver function before treatment, and monitor every 2 weeks for first year, every 4 weeks for next 6 months and then every 8 weeks thereafter (restart monitoring schedule if dose increased).
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There can be variation in the licensing of different medicines containing the same drug. Tablet CAUTIONARY AND ADVISORY LABELS 14, 25 ▶Tasmar (Mylan) Tolcapone 100 mg Tasmar 100mg tablets | 100 tablet P £95.20 DT = £95.20 DOPAMINERGIC DRUGS › DOPAMINE PRECURSORS
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Avoid abrupt withdrawal.
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Patients should be told how to recognise signs of liver disorder and advised to seek immediate medical attention if symptoms such as anorexia, nausea, vomiting, fatigue, abdominal pain, dark urine, or pruritus develop.
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100 mg 3 times a day (max. per dose 200 mg
First-line fragment. Read the complete Indications and Dose section above.
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