Carbidopa/lev/entac 31.25-125-200mg
Overview
What is this medicine?
How to Use This Medicine
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. You can take this medication with or without food. Swallow the tablet whole - do not chew, break, or crush it.
If you take an iron supplement or a multivitamin that contains iron, consult your doctor or pharmacist about how to take it with this medication. Iron may reduce the absorption of this medication in your body.
Your diet can also affect how well your body absorbs this medication. Diets high in protein, fat, or calories, as well as acidic foods, may reduce absorption. Discuss your diet with your doctor, especially if you plan to make any changes.
Do not stop taking this medication suddenly without consulting your doctor, as this may increase your risk of side effects. If you need to stop taking this medication, your doctor will instruct you on how to taper off gradually.
Continue taking this medication even when you are not experiencing symptoms. Keeping a diary of your symptoms can be helpful in tracking your progress. Take this medication at the same time every day, as directed by your doctor or healthcare provider, even if you feel well.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, away from the bathroom. Keep all medications out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are any drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses to make up for a missed dose.
Lifestyle & Tips
- Take exactly as prescribed, do not crush or chew tablets.
- Do not stop taking this medication suddenly, as it can lead to a serious condition called neuroleptic malignant syndrome-like syndrome.
- Be aware that your urine, sweat, or saliva may turn reddish-brown or black; this is a harmless effect of the medication.
- Avoid sudden changes in position (e.g., standing up quickly) to reduce dizziness or lightheadedness caused by low blood pressure.
- Report any new or worsening involuntary movements (dyskinesias) or changes in thinking, mood, or behavior (e.g., hallucinations, unusual urges) to your doctor.
- Avoid high-protein meals close to your dose, as protein can interfere with levodopa absorption. Discuss dietary considerations with your doctor or dietitian.
- Be cautious when driving or operating machinery, as this medication can cause sudden sleep attacks or drowsiness.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Condition-Specific Dosing:
Pediatric Dosing
Dose Adjustments
Renal Impairment:
Hepatic Impairment:
Pharmacology
Mechanism of Action
Pharmacokinetics
Absorption:
Distribution:
Elimination:
Pharmacodynamics
Safety & Warnings
Side Effects
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
New or worsening behavior or mood changes, including:
+ Depression
+ Thoughts of suicide
Hallucinations (seeing or hearing things that are not there)
Severe dizziness or fainting
Confusion
Vomiting blood or coffee ground-like material
Black, tarry, or bloody stools
Muscle pain or weakness, dark urine, or difficulty urinating
A skin lump or growth
Changes in the color or size of a mole
Strong, uncontrollable urges (such as eating, gambling, sex, or spending money)
New or worsening trouble controlling body movements
Chest pain or pressure
Shortness of breath
Fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Sudden, unexplained sleepiness, including falling asleep during activities like driving, eating, or talking
If you experience sudden sleepiness, do not drive or engage in activities that require alertness. Contact your doctor immediately.
Neuroleptic Malignant Syndrome (NMS)
NMS is a rare but potentially life-threatening condition that can occur when this medication is stopped suddenly or the dose is lowered. If you experience any of the following symptoms, contact your doctor immediately:
Fever
Muscle cramps or stiffness
Dizziness
Severe headache
Confusion
Changes in thinking
Fast or irregular heartbeat
Excessive sweating
Other Side Effects
Most people experience few or no side effects while taking this medication. However, some common side effects may include:
Dizziness
Sleepiness
Fatigue
Weakness
Constipation
Diarrhea
Stomach pain
Upset stomach
Nausea or vomiting
Dry mouth
Headache
Trouble sleeping
* Back pain
If you experience any of these side effects or any other symptoms that concern you, contact your doctor. They can provide guidance on managing side effects and determine if any further action is needed.
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor or report them to the FDA at 1-800-332-1088 or https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting (signs of orthostatic hypotension)
- New or worsening involuntary movements (dyskinesias)
- Hallucinations, delusions, confusion, or other psychiatric changes
- Unusual urges or behaviors (e.g., pathological gambling, increased sexual urges, compulsive shopping)
- Sudden onset of sleep during daily activities
- Severe nausea, vomiting, or diarrhea
- Muscle stiffness, fever, confusion, or rapid heart rate (signs of neuroleptic malignant syndrome-like syndrome)
- Unexplained muscle pain, tenderness, or weakness (signs of rhabdomyolysis)
Before Using This Medicine
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, including:
+ Glaucoma
+ Skin lumps or growths
+ A history of skin cancer
* If you have taken specific antidepressant medications, such as isocarboxazid, phenelzine, or tranylcypromine, within the last 14 days. Using this medication within 14 days of these drugs can lead to severe high blood pressure.
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. They will help determine if it is safe to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
When starting this medication, be cautious when driving or performing tasks that require alertness, as it may affect your ability to do so. Wait until you understand how this drug affects you before engaging in such activities.
To minimize the risk of dizziness or fainting, get up slowly from a sitting or lying position. Be particularly careful when navigating stairs.
Regular blood tests and other laboratory assessments are crucial while taking this medication. Follow your doctor's instructions for scheduling these tests. It is also important to notify all healthcare providers and laboratory personnel that you are taking this medication, as it may interfere with certain lab tests.
You may experience a decrease in the medication's effectiveness as the time for your next dose approaches. If this occurs and bothers you, discuss it with your doctor.
It may take several months to notice the full effects of this medication.
Before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that can cause drowsiness, consult with your doctor.
You may notice a dark discoloration (red, brown, or black) in your saliva, urine, or sweat. Although this is harmless, it may stain your clothing.
If you experience diarrhea or vomiting, consult your doctor promptly. It is crucial to prevent dehydration and electrolyte imbalances.
If you are pregnant, plan to become pregnant, or are breastfeeding, inform your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe dyskinesias
- Agitation, confusion, hallucinations
- Orthostatic hypotension
- Tachycardia, arrhythmias
- Nausea, vomiting
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222.
Drug Interactions
Contraindicated Interactions
- Non-selective monoamine oxidase (MAO) inhibitors (e.g., phenelzine, tranylcypromine): Risk of hypertensive crisis. Discontinue MAOIs at least 2 weeks prior to starting.
Major Interactions
- Iron salts (ferrous sulfate, gluconate): May form chelates with levodopa, reducing its absorption. Separate administration by at least 2-3 hours.
- Dopamine D2 receptor antagonists (e.g., antipsychotics like haloperidol, phenothiazines, butyrophenones, risperidone, olanzapine, clozapine): May antagonize the therapeutic effects of levodopa.
- Phenytoin, Papaverine: May reduce the therapeutic effects of levodopa.
- Metoclopramide: May increase GI motility (affecting levodopa absorption) and has dopamine antagonist properties.
Moderate Interactions
- Antihypertensives: Additive hypotensive effects, especially orthostatic hypotension.
- Tricyclic antidepressants (TCAs): May cause hypertension and dyskinesia; use with caution.
- Sympathomimetics (e.g., epinephrine, norepinephrine, dopamine, dobutamine, isoproterenol): Increased risk of arrhythmias due to enhanced cardiovascular effects of catecholamines.
- Other drugs metabolized by COMT (e.g., isoproterenol, epinephrine, norepinephrine, dopamine, dobutamine, alpha-methyldopa): Entacapone may interfere with their metabolism, potentially increasing their effects.
Minor Interactions
- Antacids: May increase entacapone absorption slightly.
Monitoring
Baseline Monitoring
Rationale: Entacapone has been associated with rare cases of liver injury.
Timing: Prior to initiation
Rationale: To assess baseline kidney function, especially in patients with severe impairment.
Timing: Prior to initiation
Rationale: Levodopa can rarely cause hemolytic anemia or leukopenia.
Timing: Prior to initiation
Rationale: To establish baseline and monitor for orthostatic hypotension.
Timing: Prior to initiation (supine and standing)
Rationale: To assess baseline for potential psychiatric adverse effects (e.g., hallucinations, psychosis, impulse control disorders).
Timing: Prior to initiation
Routine Monitoring
Frequency: At each visit, or as needed based on patient report
Target: Optimal control of symptoms with minimal dyskinesia
Action Threshold: Worsening motor symptoms or new/worsening dyskinesias require dose adjustment or consideration of adjunctive therapies.
Frequency: Regularly, especially during dose titration and if symptoms of orthostatic hypotension occur
Target: Maintain normotension, minimize orthostatic drop
Action Threshold: Significant orthostatic drop (>20 mmHg systolic or >10 mmHg diastolic) or symptomatic hypotension requires intervention (e.g., dose reduction, non-pharmacologic measures).
Frequency: At each visit
Target: Absence of new or worsening psychiatric symptoms
Action Threshold: Emergence or worsening of psychiatric symptoms requires dose adjustment or consideration of alternative therapy.
Frequency: Periodically (e.g., every 6-12 months) or if symptoms of liver dysfunction occur
Target: Within normal limits
Action Threshold: Significant elevation (e.g., >3x ULN) requires investigation and potential discontinuation.
Frequency: Periodically, especially in patients with pre-existing renal impairment
Target: Stable
Action Threshold: Significant decline may warrant re-evaluation of dosing.
Symptom Monitoring
- Dyskinesia (involuntary movements)
- Motor fluctuations (wearing-off, on-off phenomena)
- Orthostatic hypotension (dizziness, lightheadedness upon standing)
- Nausea, vomiting, diarrhea
- Hallucinations, delusions, confusion, psychosis
- Impulse control disorders (e.g., pathological gambling, hypersexuality, compulsive shopping, binge eating)
- Sleepiness, sudden onset of sleep
- Unusual urges or behaviors
- Darkening of urine, sweat, or saliva (harmless, due to entacapone metabolites)
Special Patient Groups
Pregnancy
Category C. Use only if the potential benefit justifies the potential risk to the fetus. Levodopa has been shown to be teratogenic in animals at high doses.
Trimester-Specific Risks:
Lactation
Not recommended. Levodopa is excreted into breast milk and may inhibit lactation. Entacapone is also excreted into breast milk in animals. The effects on the breastfed infant are unknown but potentially harmful.
Pediatric Use
Safety and effectiveness have not been established in pediatric patients. Not indicated for use in this population.
Geriatric Use
No specific dose adjustment is generally required based on age alone. However, elderly patients may be more sensitive to the adverse effects of levodopa, such as orthostatic hypotension, dyskinesias, and psychiatric disturbances. Monitor closely for these effects.
Clinical Information
Clinical Pearls
- This combination product is designed to reduce 'wearing-off' periods in Parkinson's patients by extending the duration of levodopa's effect.
- Patients should be advised not to crush or chew the tablets, as this can alter drug release and absorption.
- The dose and frequency are highly individualized; careful titration is necessary to optimize symptom control while minimizing dyskinesias and other side effects.
- Inform patients about the potential for harmless discoloration of urine, sweat, and saliva (reddish-brown to black).
- Counsel patients on the risk of impulse control disorders and sudden sleep attacks, and the importance of reporting these to their physician.
- High-protein meals can interfere with levodopa absorption; advise patients to take the medication at least 30 minutes before or 1 hour after such meals, or to distribute protein intake throughout the day.
Alternative Therapies
- Dopamine agonists (e.g., pramipexole, ropinirole, rotigotine)
- MAO-B inhibitors (e.g., selegiline, rasagiline, safinamide)
- Amantadine
- Anticholinergics (e.g., benztropine, trihexyphenidyl)
- COMT inhibitors (e.g., entacapone, opicapone, tolcapone - as monotherapy or with carbidopa/levodopa)
- Adenosine A2A receptor antagonists (e.g., istradefylline)