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Compare Entacapone vs. Duopa

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

Key takeaways

Entacapone (Comtan) and Duopa (carbidopa/levodopa) are both used to treat Parkinson's disease (PD), but they work differently and are used in different situations. Entacapone is a COMT inhibitor that helps carbidopa/levodopa work better by preventing levodopa from breaking down before it reaches the brain. You take it with each dose of carbidopa/levodopa. Duopa, on the other hand, is a combination of carbidopa and levodopa that is delivered continuously through a tube into your intestines for 16 hours a day, making it suitable for advanced PD. Entacapone is available in both brand-name and generic forms, while Duopa is only available as a brand-name medication. Entacapone can cause side effects like involuntary movements and nausea, while Duopa can cause serious stomach problems due to the tube placement and requires a minor procedure to insert the tube. Both medications can make you very sleepy and cause changes in behavior.

Entacapone (Comtan)
Duopa (carbidopa / levodopa)
Entacapone (Comtan)
Duopa (carbidopa / levodopa)
Summary of Entacapone vs. Duopa
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 Dopa decarboxylase inhibitor / Dopamine replacement
Prescription only
Duopa is a combination medication that contains carbidopa (a decarboxylase inhibitor) and levodopa (a dopamine replacement). It treats symptoms of advanced Parkinson's disease (PD), particularly movement problems. Duopa (carbidopa / levodopa) comes as a cassette that gets attached to an infusion pump. The infusion pump then sends the medication into the intestines through a feeding tube called a PEG-J tube. Duopa (carbidopa / levodopa) is given over 16 hours out of the day as a morning dose, a continuous dose, and any extra doses. Side effects include nausea, constipation, and involuntary muscle movements.
Indications of Entacapone vs. Duopa
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

•Movement problems related to advanced Parkinson's disease (PD)
Pros and Cons of Entacapone vs. Duopa
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 Dopa decarboxylase inhibitor / Dopamine replacement
Pros

•Given into your body continuously for 16 hours, so you don't need to remember to take pills

•Comes with extra doses in case you feel like the medication is wearing off

Cons

•Must have a minor procedure done to place the PEG-J tube in your intestines

•Risk of serious stomach problems since the infusion pump sends the medication directly into your gut

•Can cause sleepiness and changes in behavior
Common Side Effects of Entacapone vs. Duopa
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

•Issues related to tube placement (57%)

•Nausea (30%)

•Constipation (22%)

•Redness around the area where the tube is placed (19%)

•Involuntary movements (dyskinesia, 14%)

•Depression (11%)

•Discharge after the procedure where the tube is placed (11%)

•Swelling in the legs or feet (8%)

•High blood pressure (8%)

•Upper respiratory tract infection (8%)

•Mouth or throat pain (8%)

•Collapsed lung (8%)
Warnings of Entacapone vs. Duopa
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

•Stomach problems

•Sleepiness or falling asleep during activities

•A drop in blood pressure when standing

•Hallucinations, changes in behavior and thoughts, and confusion

•Difficulty controlling impulsive behavior

•Depression and suicidal thoughts

•High fevers and confusion with treatment changes

•Nerve problems

•Heart problems

•Rise in eye pressure in people with glaucoma
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Compare Entacapone vs. Duopa

Key takeaways

Summary of Entacapone vs. Duopa

Indications of Entacapone vs. Duopa

Pros and Cons of Entacapone vs. Duopa

Common Side Effects of Entacapone vs. Duopa

Warnings of Entacapone vs. Duopa

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Compare other Parkinson's Disease drugs

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