This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Catechol-O-methyltransferase inhibitors

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

  • COMT is one of the enzymes that catabolise dopamine - both within and outside the nervous system
  • COMT inhibitors therefore increase the bioavailability of dopamine (both extra and intracerebrally)
  • COMT inhibitors can reverse wearing-off effects of L-dopa without the need for an increase in daily dose
  • a common consequence of initiation of COMT inhibitor therapy is an exacerbation of L-dopa induced side effects e.g. dyskinesias; these should settle when the L-dopa dose has been appropriately adjusted
  • other side effects of COMT inhibitors include:
    • diarrhoea - often self-limiting - occurs in approximately 10% of patients on standard dose
    • may be some orange discoloration of patient's urine

NICE guidance states (1):

  • COMT inhibitors may be used to reduce motor fluctuations in people with later Parkinson's disease (PD)
  • in view of problems with reduced concordance, people with later PD taking entacapone should be offered a triple combination preparation of levodopa, carbidopa and entacapone
  • tolcapone should only be used after entacapone has failed in people with later PD due to lack of efficacy or side effects. Liver function tests are required every 2 weeks during the first year of therapy, and thereafter in accordance with the 'Summary of product characteristics'

Reference:

  1. NICE (June 2006). Parkinson's disease

Related pages

Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.