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.
The symptoms of Parkinson's disease (PD) are caused by low dopamine levels in the brain. People with PD often take a medication called levodopa. Levodopa turns into dopamine in the brain. This helps relieve PD symptoms. But, there's a protein in the body that breaks down levodopa before it can reach the brain. This protein is called catechol-O-methyltransferase (COMT). COMT causes levodopa to not work as well to relieve PD symptoms.
Entacapone (Comtan) is a COMT inhibitor. It blocks the COMT protein so less levodopa gets broken down in your body. When you take entacapone (Comtan) with carbidopa/levodopa, levodopa can reach and stay at higher levels in the brain. This allows more levodopa to turn into dopamine to relieve PD symptoms.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Absence of or decrease in body movements
hyperactivity
increase in body movements
seeing, hearing, or feeling things that are not there
twisting
twitching
uncontrolled repetitive movements of the tongue, lips, face, arms, or legs
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Acid or sour stomach
belching
bruising
burning feeling in the chest or stomach
difficult or labored breathing
indigestion
irritability
loss of strength or energy
muscle pain or weakness
passing gas
restlessness
sleepiness or unusual drowsiness
small, red spots on the skin
stomach discomfort, upset, or tenderness
sweating increased
tightness in the chest
trouble sleeping
unusual or unpleasant (after) taste
unusual weak feeling
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
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
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
Entacapone (Comtan) can make you very sleepy. It can sometimes even make you fall asleep suddenly with or without warning. Don't drive or do anything that requires concentration until you know how this medication affects you. Speak with your provider if you feel very sleepy during the day or fall asleep suddenly while you're taking entacapone (Comtan).
Entacapone (Comtan) can make you feel lightheaded or dizzy when you stand up from a sitting or lying down position. This can lead to fainting. To avoid falling, stand up slowly or hold onto something stable when you get up after sitting or lying down.
Entacapone (Comtan) can cause nausea, especially after you first start the medication. If this becomes bothersome, let your provider know. They can recommend ways to help manage nausea from the medication, such as staying hydrated and eating smaller meals portions.
You might have more trouble controlling your body's movements (dyskinesia) after starting entacapone (Comtan). If this becomes bothersome, let your provider know so they can prescribe a lower dose of the medication.
Although it's harmless, entacapone (Comtan) can change the color of your urine to a brownish orange color.
Entacapone (Comtan) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Already feeling drowsy | History of sleep problems | Taking sedatives or medications that make you drowsy
Entacapone (Comtan) and carbidopa/levodopa medications can make you fall asleep out of nowhere, even if you don't feel sleepy. This can happen at any time of day and can lead to accidental injuries. Because of this risk, be careful driving or doing things that require you to focus while you're taking entacapone (Comtan). Make sure you know how this medication affects you first before doing these activities. If you normally feel sleepy or if you've fallen asleep suddenly in the past, it might be safer if you avoid driving while you're taking entacapone (Comtan). Let your provider know if you feel very sleepy during the daytime or if you fall asleep during activities where you need to concentrate while you're taking entacapone (Comtan).
Risk factors: History of low blood pressure
Entacapone (Comtan) can boost the effects of carbidopa/levodopa medications. This can raise your risk of low blood pressure. Taking entacapone (Comtan) can cause your blood pressure to drop when you stand from a sitting or lying down position. This can lead to fainting. To lower your risk of falling, get up slowly when you stand from a sitting or lying down position. Let your provider know if your blood pressure is lower than it usually is or if you feel dizzy while you're taking entacapone (Comtan).
Risk factors: History of certain mental health conditions
Some people taking entacapone (Comtan) and medications that raise dopamine levels have had hallucinations. They've also reported changes in behavior and thinking, such as paranoia, delusions, confusion, aggressive behavior, uneasiness, and less awareness of their surroundings. Generally, these symptoms can occur shortly after you start taking these medications or after your dose is raised. Because of this risk, you shouldn't take entacapone (Comtan) if you have certain mental health conditions. In addition, some medications used for mental health conditions, such as haloperidol (Haldol) or perphenazine, can worsen your Parkinson's disease and might affect how well entacapone (Comtan) works. Let your provider know if you experience any changes in behavior or thinking during entacapone (Comtan) treatment.
Entacapone (Comtan) and other medications for Parkinson's disease can cause impulsive behavior. These changes in behavior include strong sexual or gambling urges, urges to spend a lot of money, and other urges. These medications can also make it hard to control these urges. If these urges start to have a negative impact on your life, let your provider know. You might not be aware that you have these urges while taking entacapone (Comtan), so your provider might ask you if you've recently had these behaviors at your next visit. If these urges occur, your provider might consider lowering your dose or stopping treatment.
Entacapone (Comtan) can cause diarrhea. In studies, most cases of diarrhea were mild or moderate, but a few were severe. Usually, this side effect happens within the first few months after starting entacapone (Comtan). But, it can start as early as the first week or as late as several months after starting. Diarrhea can also be a sign of inflammation in your colon (colitis). If your colon is inflamed, you can have moderate-to-severe diarrhea with watery, non-bloody stool. Diarrhea can lead to weight loss, dehydration, and low potassium levels. Make sure to drink plenty of fluids to avoid getting dehydrated while you're taking entacapone (Comtan). If you have any symptoms of diarrhea, colitis, or dehydration while you're taking entacapone (Comtan), let your provider know. Typically, these symptoms get better or go away after you stop the medication.
Some people taking entacapone (Comtan) have reported severe muscle damage (rhabdomyolysis). Sometimes, this can lead to kidney damage. It's not clear whether entacapone (Comtan) affects the risk of this muscle damage. But, it might be related to the involuntary movements (dyskinesia) you might experience with treatment. Let your provider know right away if you have muscle aches, soreness, or cramping, dark-colored urine, or feel weak. These can be signs and symptoms of serious muscle damage.
Although rare, some people taking medications for Parkinson's disease can develop a serious condition called neuroleptic malignant syndrome (NMS). Symptoms include very high fevers, irregular pulse, muscle stiffness, and confusion. Most times, symptoms happen when the medication is stopped or when the dose is lowered suddenly.
It's not clear whether entacapone (Comtan) plays a role in causing NMS. There also haven't been any reports of people taking entacapone (Comtan) who developed this condition in studies. But it's important to be aware of these symptoms so you can get treated as soon as you notice them. Don't stop taking entacapone (Comtan) or lower your dose without talking to your provider so they can tell you how to do so safely.
Entacapone (Comtan) works by blocking the COMT protein. But, this protein normally helps break down other medications, such as apomorphine (Apokyn) and epinephrine (Epipen). When entacapone (Comtan) is taken with these medications, they can stay in the body longer and raise your risk of side effects like faster heart rate, irregular heart rhythm, and changes in blood pressure.
In addition, it's generally not recommended to take entacapone (Comtan) with non-selective monoamine oxidase inhibitors (MAOIs), such as phenelzine (Nardil). Non-selective MAOIs can also block the breakdown of important hormones and medications like those listed above. It's important to note that some medications for Parkinson's disease, like rasagiline (Azilect) and selegiline, are selective MAO-B inhibitors. These medications can be taken together with entacapone (Comtan).
Dosage | Quantity | Price as low as | Price per unit |
---|---|---|---|
200mg | 120 tablets | $44.40 | $0.37 |
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Parkinson's disease (PD)
Parkinsonism (conditions that cause people to have signs and symptoms of PD, including slowness, stiffness, shakiness, and imbalance)
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Labeit, B., et al. (2022). Dysphagia for medication in Parkinson’s disease. npj Parkinson's Disease.
MedlinePlus. (2021). Low blood potassium.
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