Sounds like 'TOLL-cup-own'

Tolcapone is used to treat the symptoms of Parkinson's disease. Find out how to take it safely and possible side effects.Tolcapone is commonly called Tasmar.

Type of medicine Also called
  • Dopaminergic medicine
  • Belongs to a group of medicines called COMT blockers
  • Used to treat Parkinson's disease
  • Tasmar®

What is tolcapone?

Tolcapone is used together with levodopa + carbidopa or levodopa + benserazide to treat the symptoms of Parkinson's disease, or Parkinson-like symptoms such as tremor, shakiness, stiffness, and difficulty moving.

Many people taking levodopa for Parkinson's disease have problems with the effects of the levodopa wearing off between doses. This causes the Parkinson's symptoms to return or worsen. Tolcapone blocks a certain natural substance (COMT enzyme) that breaks down the levodopa in the body. This allows the levodopa to last longer so that it doesn't wear off before the next dose.

In New Zealand tolcapone is available as tablets.


  • The usual dose of tolcapone is 100 milligrams three times a day. Some people may need 200 milligrams three times a day.
  • You will be started on a low dose, and then your doctor might increase your dose to control your symptoms.
  • Always take your tolcapone exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much tolcapone to take, how often to take it, and any special instructions.

How to take tolcapone

  • Timing: Take your tolcapone at the same times each day. You can take tolcapone with or without food. Take your first tolcapone dose of the day at the same time as your levodopa + carbidopa dose or levodopa + benserazide dose.
  • Swallow the tablets whole, with water. Do not break or crush the tablets, and do not take any tablets that are damaged, because they have a bitter taste.
  • Limit or avoid alcohol while taking tolcapone. It increases your chance of side effects.
  • Missed dose: If you do miss a dose and it is nearly time for your next dose, skip the missed dose and take your next dose at the usual time. Otherwise, take the missed dose as soon as you remember. Do not take two doses at the same time.
  • Keep taking tolcapone regularly. Do not stop taking tolcapone without talking to your doctor first. Stopping treatment suddenly can cause serious problems.

Side effects

Like all medicines, tolcapone can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Changes in the colour of your urine, sweat or saliva — it may turn red, brown or black
  • This is harmless and is nothing to worry about
  • Feeling or being sick (nausea)
  • This is common when you first start taking tolcapone
  • Try taking your dose with food
  • Falling asleep suddenly during daily activities (such as talking on the phone, or driving)
  • This sleep effect can occur without any feelings of drowsiness beforehand, and can happen anytime during treatment with this medication
  • Tell your doctor
  • Do not drive or use tools until you know how this medicine affects you and until these have stopped happening
  • Avoid drinking alcohol
  • Feeling dizzy or faint when you stand up (due to a sudden drop in blood pressure)
  • Be careful when getting up from either lying down or sitting, to avoid falls
  • Tell your doctor
  • Signs of problems with your liver such as yellowing of the skin or eyes, dark urine, itchy skin, pain in the abdomen
  • Tell your doctor immediately or ring HealthLine 0800 611 116


Tolcapone interacts with a number of important medications and herbal supplements, so check with your doctor or pharmacist. 

Learn more

The following links provide further information on tolcapone.


Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 08 Dec 2016