Generic Name: entacapone

Brand and Other Names: Comtan

Drug Class: Anti-Parkinson Agent, COMT Inhibitor

What is entacapone, and what is it used for?

Entacapone is a prescription medication used together with carbidopa and levodopa to treat “wearing-off” symptoms of Parkinson's disease, such as stiffness, tremors, muscle spasms, and poor muscle control. 


  • Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.
  • People with Parkinson's disease may have a higher risk of skin cancer (melanoma). Talk to your doctor about this risk and what skin symptoms to watch for. You may need to have regular skin exams.
  • This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Entacapone may cause you to fall asleep suddenly, even after feeling alert.
  • Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.
  • Avoid drinking alcohol. It can increase some of the side effects of entacapone.

Do not take if you have: 

  • Hypersensitivity to entacapone

What are the side effects of entacapone?

Common side effects of entacapone include:

Serious side effects of entacapone include:

  • hives
  • difficult breathing,
  • swelling of the face, lips, tongue, or throat,
  • agitation, confusion, unusual thoughts, or behavior,
  • hallucinations (hearing or seeing something that is not there);
  • very stiff (rigid) muscles, high fever, sweating, fast or uneven heartbeats, tremors, light-headedness
  • severe or ongoing diarrhea,
  • restless muscle movements in the eyes, tongue, jaw, or neck (or worsening of Parkinson’s symptoms); or
  • unexplained muscle pain, tenderness, or weakness especially if you also have a fever, unusual tiredness, and dark-colored urine.

Rare side effects of entacapone include:

  • none

Seek medical care or call 911 at once if you have the following serious side effects:

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug.

Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

What is the dosage for entacapone?

Adult dosage


  • 200 mg

Parkinson disease

Adult dosage

  • Oral: 200 mg with each dose of levodopa/carbidopa, up to a maximum of 8 times daily (maximum daily dose: 1600 mg daily).

What drugs interact with entacapone?

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first

  • Entacapone has severe interactions with the following drugs:
    • isocarboxazid
    • lonafarnib
    • phenelzine
    • tranylcypromine
  • Entacapone has serious interactions with the following drugs:
    • infigratinib
    • lurbinectedin
    • metoclopramide intranasal
    • pacritinib
    • ropeginterferon alfa 2b
  • Entacapone has moderate interactions with the following drugs:
    • atonement
    • daridorexant
    • difelikefalin
    • dobutamine
    • dopamine
    • epinephrine
    • epinephrine inhaled
    • epinephrine racemic
    • finerenone
    • ganaxolone
    • isavuconazonium sulfate
    • isoproterenol
    • lefamulin
    • lumateperone
    • mavacamten
    • methyldopa
    • norepinephrine
    • oliceridine
    • voclosporin
    • warfarin
  • Entacapone has minor interactions with no other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. 

Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, or if you have health questions or concerns.

Pregnancy and breastfeeding

Pregnancy and Lactation

  • It is not known whether entacapone will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.



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Entacapone is a prescription medication used together with carbidopa and levodopa to treat “wearing-off” symptoms of Parkinson's disease, such as stiffness, tremors, muscle spasms, and poor muscle control. Common side effects of entacapone include dizziness, drowsiness, nausea, vomiting, stomach pain, diarrhea, dry mouth, or uncontrolled muscle movements. Avoid drinking alcohol due to risk of increased side effects. Consult your doctor if pregnant or breastfeeding.

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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Medically Reviewed on 11/3/2022