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Home > Wellness > Health Library > COMT Inhibitors for Parkinson's Disease
Catechol O-methyltransferase (COMT)
inhibitors allow a larger amount of levodopa to reach the brain, which raises
dopamine levels there. They help provide a more stable, constant supply of
levodopa, which makes its beneficial effects last longer.
COMT inhibitors are always taken in combination with levodopa. They do not have any effect on Parkinson's disease symptoms by themselves.
COMT inhibitors are used in
combination with levodopa to treat people with
Parkinson's disease who have:
COMT inhibitors are helpful to many
people who have Parkinson's disease. Treatment with tolcapone or entacapone
A combination medicine (Stalevo) combines
entacapone, levodopa, and carbidopa. This may be more convenient for some
people, because they would need to take only one pill instead of two.
All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.
Here are some important things to think about:
Call 911 or other emergency services right away if you have:
Call your doctor if you have:
Common side effects of this medicine include:
Call your doctor right away if you have:
Reference for a full list of side effects. (Drug Reference is not available in
Both of these drugs can cause a change in the color of your urine. Entacapone can turn your urine brownish orange. Tolcapone can turn your urine bright yellow. You do not need to worry about this. But if you are taking tolcapone and your urine turns dark brown along with the other signs of liver damage listed above, call your doctor immediately.
Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.
There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.
Complete the new medication information form (PDF)new medication information form (PDF)(What is a PDF document?) to help you understand this medication.
Stowe R, et al. (2010). Evaluation of the efficacy and safety of adjuvant treatment to levodopa therapy in Parkinson's disease patients with motor complications. Cochrane Database of Systematic Reviews (7).
December 5, 2012
Anne C. Poinier, MD - Internal Medicine & G. Frederick Wooten, MD - Neurology
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