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Compare Entacapone vs. Carbidopa

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Entacapone (Comtan) and Carbidopa (Lodosyn) are both used to treat symptoms of Parkinson's disease (PD), but they work in different ways. Entacapone is a COMT inhibitor that helps levodopa stay in your body longer by blocking the COMT protein, which breaks down levodopa. This means you need to take it with each dose of carbidopa/levodopa for it to work. On the other hand, Carbidopa is a decarboxylase inhibitor that helps more levodopa reach your brain by preventing its breakdown before it gets there. This allows you to take a lower dose of levodopa, reducing some of its side effects. Entacapone and Carbidopa are both available in both brand-name and generic forms. Both medications can cause side effects like involuntary movements and nausea, but Entacapone can also cause diarrhea and stomach pain, while Carbidopa can lead to psychotic behavior and depression. Additionally, both medications can make you very sleepy or cause you to fall asleep suddenly, so you should be cautious when driving or doing activities that require concentration.

  • Entacapone (Comtan)
    Carbidopa (Lodosyn)
  • Entacapone (Comtan)
    Carbidopa (Lodosyn)

  • Summary of Entacapone vs. Carbidopa

    Summary for COMT inhibitor
    Prescription only

    Entacapone (Comtan) is used for Parkinson's disease (PD) and helps relieve symptoms like shakiness and slowed movement. It's used along with the combination medication carbidopa/levodopa. Entacapone (Comtan) is a good option for people whose levodopa wears off before their next dose ("wearing-off" periods). But, this medication has to be taken every time you take carbidopa/levodopa for it to work properly. Some side effects include involuntary movements (dyskinesia) and nausea. Entacapone (Comtan) is available as a brand-name and generic medication.

    Summary for Decarboxylase inhibitor
    Prescription only

    Carbidopa (Lodosyn) is taken with Sinemet (carbidopa / levodopa) or levodopa alone to treat adults with symptoms of Parkinson's disease (PD), like shakiness and slowed movement. The medication belongs to the decarboxylase inhibitor class and it works by helping levodopa better travel into your brain so it can relieve your symptoms. This might allow some people to take a lower dose of levodopa, which can lower some of its side effects. Side effects include fatigue, a drop in blood pressure, changes in urination, and weight changes.

  • Indications of Entacapone vs. Carbidopa

    Indications for
    •Relief of "wearing-off" symptoms in people with Parkinson's disease who are taking carbidopa/levodopa medications (e.g., Sinemet, Rytary)
    Indications for

    When taken together with levodopa or Sinemet (carbidopa / levodopa):

    •Parkinson's disease (PD)
    •Parkinsonism

  • Pros and Cons of Entacapone vs. Carbidopa

    Pros and Const for COMT inhibitor
    Pros
    •Helps carbidopa/levodopa relieve your PD symptoms better
    •Can be useful for people with advanced PD or people who experience "wearing-off" periods with their carbidopa/levodopa
    •Can take with or without food
    Cons
    •Must take with every dose of carbidopa/levodopa to see an effect on PD symptoms; it has no effect when it's taken alone
    •Can cause involuntary movements or other movement problems
    •Can cause nausea, especially when you first start taking the medication
    Pros and Const for Decarboxylase inhibitor
    Pros
    •Helps levodopa relieve your Parkinson's symptoms
    •Might allow some people to take a lower dose of levodopa, which can ease side effects like nausea and vomiting
    •Can split the tablet in half as needed
    •Available in a lower-cost generic form
    Cons
    •Doesn't work when used alone and must be taken with levodopa
    •Might need to be taken multiple times per day
    •Can cause psychotic behavior and strong urges
    •Can make you fall asleep suddenly with or without warning

  • Common Side Effects of Entacapone vs. Carbidopa

    Common Side Effects for
    •Involuntary movements (dyskinesia, 25%)
    •Nausea (14%)
    •Muscle spasms (hyperkinesia, 10%)
    •Changes in the color of your urine (10%)
    •Diarrhea (10%)
    •Slowed muscle movements (hypokinesia, 9%)
    •Stomach pain (8%)
    •Dizziness (8%)
    Common Side Effects for
    •Involuntary movements (dyskinesia or dystonia)
    •Nausea

  • Warnings of Entacapone vs. Carbidopa

    Common Side Effects for
    •Sleepiness or falling asleep while doing daily activities
    •Low blood pressure and fainting
    •Hallucinations and changes in behavior and thoughts
    •Difficulty controlling impulsive behavior
    •Diarrhea and inflamed colon (colitis)
    •Muscle damage (rhabdomyolysis)
    •High fevers and confusion
    •Interactions with other medications
    Common Side Effects for
    •Sleepiness or falling asleep during activities
    •High fevers and confusion (from levodopa)
    •Impulsive behavior
    •Hallucinations and changes in behavior and thoughts
    •Depression and suicidal thoughts and behavior
    •Skin cancer

  • Prices with our coupons for Entacapone vs. Carbidopa

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    Learn more about Carbidopa

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