Carbidopa/levodopa 25mg-250mg Tabs
It is used to treat Parkinson's disease.It is used to treat signs like Parkinson's disease caused by other health problems.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Anti-Parkinsonian Agent
Pharmacologic Class
Dopamine Precursor / DOPA Decarboxylase Inhibitor
Pregnancy Category
Category C
FDA Approved
Jun 1975
DEA Schedule
Not Controlled
Overview
What is this medicine?
Carbidopa/levodopa is a medication used to treat Parkinson's disease. Parkinson's disease is caused by a lack of a chemical called dopamine in the brain. Levodopa turns into dopamine in your brain, helping to improve your movement and reduce stiffness. Carbidopa helps more levodopa get to your brain by preventing it from breaking down too soon in your body, which also helps reduce side effects like nausea.
How to Use This Medicine
Taking Your Medication Correctly
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. If you have tablets with a score line, you can split them along the line if needed.
Important Interactions to Consider
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. Additionally, a diet high in protein, fat, or calories, as well as consuming acidic foods, may also affect how well your body absorbs this medication. Discuss your diet with your doctor, especially if you plan to make any changes.
Maintaining Your Treatment Schedule
Continue taking this medication even when you're not experiencing symptoms. Keeping a diary of your symptoms can be helpful. Take this medication at the same time every day, as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a safe location, out of 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're unsure about the best way to dispose of your medication, consult your pharmacist. You may also have access to 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's 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 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. If you have tablets with a score line, you can split them along the line if needed.
Important Interactions to Consider
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. Additionally, a diet high in protein, fat, or calories, as well as consuming acidic foods, may also affect how well your body absorbs this medication. Discuss your diet with your doctor, especially if you plan to make any changes.
Maintaining Your Treatment Schedule
Continue taking this medication even when you're not experiencing symptoms. Keeping a diary of your symptoms can be helpful. Take this medication at the same time every day, as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a safe location, out of 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're unsure about the best way to dispose of your medication, consult your pharmacist. You may also have access to 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's 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.
Lifestyle & Tips
- Take this medication exactly as prescribed by your doctor. Do not take more or less, or take it more often than prescribed.
- Do not stop taking this medication suddenly, as it can lead to severe withdrawal symptoms (neuroleptic malignant syndrome-like syndrome). Any changes to your dose should be done under medical supervision.
- Take with food to reduce nausea, but avoid high-protein meals (e.g., large amounts of meat, dairy) as they can reduce the absorption of levodopa. If you experience 'wearing-off' effects, discuss with your doctor about timing your protein intake.
- Stand up slowly from a sitting or lying position to avoid dizziness or lightheadedness (orthostatic hypotension).
- Be aware that your urine, sweat, or saliva may turn dark (red, brown, or black). This is a harmless side effect.
- Avoid taking iron supplements or multivitamins containing iron at the same time as this medication. Separate by at least 2-3 hours.
- Report any new or worsening involuntary movements (dyskinesias) or changes in your mental state (e.g., hallucinations, confusion, unusual urges) to your doctor immediately.
Available Forms & Alternatives
Available Strengths:
- Carbidopa/levodopa 25mg-250mg Tabs
- Carbidopa/levodopa ODT 25-100mg Tab
- Carbidopa/levodopa ODT 25-250mg Tab
- Carbidopa/levodopa ODT 10-100mg Tab
- Carbidopa/levod 25-100mg Scored T
- Carbidopa/levodopa 10-100mg Tabs
- Carbidopa/levodopa 25-100mg Tabs
- Carbi/levo CR 25-100mg Tb
- Carbidopa/levodopa 50-200mg CR Tabs
- Carbidopa/levodopa 25-100mg Tabs
- Carbidopa/levodopa 10-100mg Tabs
- Carbidopa/levodopa 25mg-250mg Tabs
- Carbidopa/levodopa 50-200mg CR Tabs
Dosing & Administration
Adult Dosing
Standard Dose:
Initial: Carbidopa/Levodopa 25 mg/100 mg orally three times daily. Titrate gradually.
Dose Range:
25 - 2000 mg
Condition-Specific Dosing:
Parkinson's Disease:
Initial: 25 mg carbidopa / 100 mg levodopa orally three times daily. Increase by 1 tablet every 1-2 days as tolerated, up to 8 tablets per day (200 mg carbidopa / 800 mg levodopa). Max daily dose: 200 mg carbidopa / 2000 mg levodopa. Doses should be individualized based on patient response and tolerability. Doses should be divided and taken with food to minimize GI upset, but avoid high protein meals.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established (generally not recommended for use in patients under 18 years of age)
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment recommended, but monitor for adverse effects.
Moderate:
No specific dose adjustment recommended, but monitor for adverse effects. Titrate cautiously.
Severe:
No specific dose adjustment recommended, but monitor for adverse effects. Titrate cautiously.
Dialysis:
Not dialyzable to a significant extent. No specific dose adjustment for dialysis patients, but monitor closely.
Hepatic Impairment:
Mild:
No specific dose adjustment recommended, but monitor for adverse effects.
Moderate:
No specific dose adjustment recommended, but monitor for adverse effects. Titrate cautiously.
Severe:
No specific dose adjustment recommended, but monitor for adverse effects. Titrate cautiously.
Pharmacology
Mechanism of Action
Carbidopa inhibits peripheral DOPA decarboxylase, an enzyme that converts levodopa to dopamine in the periphery. This allows more levodopa to cross the blood-brain barrier (BBB) for conversion to dopamine in the central nervous system (CNS). Levodopa is a metabolic precursor of dopamine, which is deficient in the brains of patients with Parkinson's disease. By increasing dopamine levels in the brain, it helps to alleviate the motor symptoms of Parkinson's disease.
Pharmacokinetics
Absorption:
Bioavailability:
Levodopa: Highly variable, approximately 30% (oral, without carbidopa); significantly increased with carbidopa. Carbidopa: Approximately 40-70%.
Tmax:
Levodopa: 0.5-2 hours (with carbidopa). Carbidopa: 1.5-5 hours.
FoodEffect:
High-protein meals can significantly reduce levodopa absorption and peak plasma concentrations due to competition for transport across the intestinal wall and BBB. Taking with food can reduce GI upset, but avoid high protein meals.
Distribution:
Vd:
Levodopa: 0.9-1.6 L/kg. Carbidopa: Not well characterized, but primarily distributed to extracellular fluid.
ProteinBinding:
Levodopa: Low (<10%). Carbidopa: Approximately 36%.
CnssPenetration:
Levodopa: Yes (crosses BBB). Carbidopa: No (does not cross BBB significantly).
Elimination:
HalfLife:
Levodopa: Approximately 1-2 hours (with carbidopa). Carbidopa: Approximately 2-3 hours.
Clearance:
Levodopa: Approximately 0.3 L/hr/kg. Carbidopa: Not well characterized.
ExcretionRoute:
Primarily renal (urine).
Unchanged:
Levodopa: <1% (without carbidopa); higher with carbidopa. Carbidopa: Approximately 50% excreted unchanged in urine.
Pharmacodynamics
OnsetOfAction:
Approximately 30-60 minutes (oral).
PeakEffect:
Approximately 1-2 hours after dose.
DurationOfAction:
Approximately 3-6 hours, highly variable and can shorten with disease progression ('wearing-off' phenomenon).
Safety & Warnings
Side Effects
Serious Side Effects: Seek Medical Help Right Away
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 immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness or swelling of the mouth, face, lips, tongue, or throat
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Fainting or changes in vision
New or worsening behavioral or mood changes, such as:
+ Depression or thoughts of suicide
Hallucinations (seeing or hearing things that are not there)
Confusion
Strong, uncontrollable urges (e.g., eating, gambling, sex, or spending money)
A new skin lump or growth, or changes in the color or size of a mole
Difficulty controlling body movements (new or worsening)
Eyelid twitching or muscle twitching
Stomach pain, black, tarry, or bloody stools, vomiting blood, or coffee ground-like vomit
Chest pain or pressure, rapid or irregular heartbeat
Fever, chills, sore throat, unexplained bruising or bleeding, or feeling extremely tired or weak
Dark urine, yellow skin or eyes, changes in vision, eye pain, or severe eye irritation
Shortness of breath
Sudden, uncontrollable sleepiness, even during activities like driving, eating, or talking (this can occur up to 1 year after starting the medication)
If you experience sudden sleepiness, do not drive or engage in activities that require alertness. Contact your doctor immediately if you experience this side effect or feel extremely sleepy.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it is essential to report any concerns to your doctor. If you experience any of the following side effects, contact your doctor if they bother you or do not go away:
Bad dreams
Constipation
Dizziness or drowsiness
Dry mouth
Headache
Difficulty sleeping
Some products may cause a dark red, brown, or black color to appear in your saliva, urine, or sweat (this is harmless but may stain clothing)
* Upset stomach or vomiting
This is not an exhaustive list of possible side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
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 immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness or swelling of the mouth, face, lips, tongue, or throat
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Fainting or changes in vision
New or worsening behavioral or mood changes, such as:
+ Depression or thoughts of suicide
Hallucinations (seeing or hearing things that are not there)
Confusion
Strong, uncontrollable urges (e.g., eating, gambling, sex, or spending money)
A new skin lump or growth, or changes in the color or size of a mole
Difficulty controlling body movements (new or worsening)
Eyelid twitching or muscle twitching
Stomach pain, black, tarry, or bloody stools, vomiting blood, or coffee ground-like vomit
Chest pain or pressure, rapid or irregular heartbeat
Fever, chills, sore throat, unexplained bruising or bleeding, or feeling extremely tired or weak
Dark urine, yellow skin or eyes, changes in vision, eye pain, or severe eye irritation
Shortness of breath
Sudden, uncontrollable sleepiness, even during activities like driving, eating, or talking (this can occur up to 1 year after starting the medication)
If you experience sudden sleepiness, do not drive or engage in activities that require alertness. Contact your doctor immediately if you experience this side effect or feel extremely sleepy.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it is essential to report any concerns to your doctor. If you experience any of the following side effects, contact your doctor if they bother you or do not go away:
Bad dreams
Constipation
Dizziness or drowsiness
Dry mouth
Headache
Difficulty sleeping
Some products may cause a dark red, brown, or black color to appear in your saliva, urine, or sweat (this is harmless but may stain clothing)
* Upset stomach or vomiting
This is not an exhaustive list of possible side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting (orthostatic hypotension)
- New or worsening uncontrolled, involuntary movements (dyskinesias)
- Hallucinations (seeing or hearing things that are not there)
- Confusion or unusual thoughts
- Sudden onset of sleep during daily activities
- Unusual urges or behaviors (e.g., increased gambling, hypersexuality, compulsive shopping, binge eating)
- Severe nausea or vomiting that does not improve
- Muscle stiffness, fever, or altered consciousness (signs of neuroleptic malignant syndrome-like syndrome if stopped abruptly)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, such as:
+ Glaucoma
+ Skin lumps or growths
+ A history of skin cancer
Current or recent use of specific medications, including:
+ Reserpine or tetrabenazine
+ Linezolid or methylene blue
+ Certain antidepressants or Parkinson's disease medications taken within the last 14 days, such as:
- Isocarboxazid
- Phenelzine
- Tranylcypromine
- Selegiline
- Rasagiline (note: taking these medications with this drug can lead to very high blood pressure)
Use of any other medications that contain the same active ingredient as this drug
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health conditions 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 consulting your doctor first.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, such as:
+ Glaucoma
+ Skin lumps or growths
+ A history of skin cancer
Current or recent use of specific medications, including:
+ Reserpine or tetrabenazine
+ Linezolid or methylene blue
+ Certain antidepressants or Parkinson's disease medications taken within the last 14 days, such as:
- Isocarboxazid
- Phenelzine
- Tranylcypromine
- Selegiline
- Rasagiline (note: taking these medications with this drug can lead to very high blood pressure)
Use of any other medications that contain the same active ingredient as this drug
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health conditions 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 consulting your doctor first.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent any potential interactions with other treatments.
To minimize the risk of accidents, avoid driving and engaging in activities that require your full attention until you understand how this medication affects you. Additionally, to reduce the likelihood of dizziness or fainting, stand up slowly after sitting or lying down, and exercise caution when climbing stairs.
This medication may interfere with certain laboratory tests, so it is crucial to notify all your healthcare providers and laboratory personnel that you are taking this drug. Regular blood tests and eye exams, as recommended by your doctor, are also necessary to monitor your condition.
If you have diabetes (high blood sugar), consult with your doctor to determine the most suitable glucose tests for you to use. You may experience a decrease in the medication's effectiveness as the time for your next dose approaches, a phenomenon known as "wearing off." If this occurs and bothers you, inform your doctor.
Before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may impair your reactions, discuss the potential risks with your doctor. People with Parkinson's disease may have an increased risk of developing a type of skin cancer called melanoma, although it is unclear whether this medication contributes to this risk. To be safe, schedule regular skin exams with your doctor while taking this medication.
Do not abruptly stop taking this medication or reduce your dosage without consulting your doctor, as this may lead to severe side effects, including fever, muscle cramps or stiffness, dizziness, severe headache, confusion, altered thinking, abnormal heartbeat, or excessive sweating. If you experience any of these symptoms, contact your doctor immediately.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor to discuss the potential benefits and risks of this medication for both you and your baby.
To minimize the risk of accidents, avoid driving and engaging in activities that require your full attention until you understand how this medication affects you. Additionally, to reduce the likelihood of dizziness or fainting, stand up slowly after sitting or lying down, and exercise caution when climbing stairs.
This medication may interfere with certain laboratory tests, so it is crucial to notify all your healthcare providers and laboratory personnel that you are taking this drug. Regular blood tests and eye exams, as recommended by your doctor, are also necessary to monitor your condition.
If you have diabetes (high blood sugar), consult with your doctor to determine the most suitable glucose tests for you to use. You may experience a decrease in the medication's effectiveness as the time for your next dose approaches, a phenomenon known as "wearing off." If this occurs and bothers you, inform your doctor.
Before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may impair your reactions, discuss the potential risks with your doctor. People with Parkinson's disease may have an increased risk of developing a type of skin cancer called melanoma, although it is unclear whether this medication contributes to this risk. To be safe, schedule regular skin exams with your doctor while taking this medication.
Do not abruptly stop taking this medication or reduce your dosage without consulting your doctor, as this may lead to severe side effects, including fever, muscle cramps or stiffness, dizziness, severe headache, confusion, altered thinking, abnormal heartbeat, or excessive sweating. If you experience any of these symptoms, contact your doctor immediately.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor to discuss the potential benefits and risks of this medication for both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe involuntary movements (dyskinesias)
- Palpitations or irregular heartbeat
- Orthostatic hypotension
- Confusion, agitation, or hallucinations
- Nausea and vomiting
What to Do:
Seek immediate medical attention or call a poison control center. Call 1-800-222-1222. Treatment is supportive, including gastric lavage, IV fluids, and careful monitoring of cardiac and respiratory function. Antiarrhythmics may be needed for cardiac irregularities.
Drug Interactions
Contraindicated Interactions
- Non-selective monoamine oxidase inhibitors (MAOIs) (e.g., phenelzine, tranylcypromine) - risk of hypertensive crisis. Must discontinue MAOIs at least 2 weeks prior to initiating carbidopa/levodopa.
Major Interactions
- Antipsychotics (e.g., haloperidol, chlorpromazine, risperidone, olanzapine) - may antagonize the effects of levodopa due to dopamine receptor blockade, worsening Parkinsonian symptoms.
- Iron salts (ferrous sulfate, gluconate) - can chelate levodopa, reducing its absorption. Separate administration by at least 2-3 hours.
- Metoclopramide - may antagonize the effects of levodopa and increase risk of dyskinesia.
- Pyridoxine (Vitamin B6) - large doses can reverse the effects of levodopa by increasing peripheral DOPA decarboxylase activity, unless carbidopa is present in sufficient amounts.
Moderate Interactions
- Antihypertensives - increased risk of orthostatic hypotension.
- Tricyclic antidepressants (TCAs) - may rarely increase risk of hypertension and dyskinesia.
- Sympathomimetics (e.g., epinephrine, norepinephrine, dopamine) - increased risk of arrhythmias.
- High-protein diet - reduces levodopa absorption and efficacy.
Minor Interactions
- Antacids - may slightly increase levodopa absorption.
Monitoring
Baseline Monitoring
Motor function assessment (e.g., UPDRS)
Rationale: To establish baseline severity of Parkinson's symptoms and track response to therapy.
Timing: Prior to initiation of therapy.
Mental status/Cognitive function
Rationale: To assess for baseline cognitive impairment and monitor for drug-induced psychiatric side effects (e.g., hallucinations, confusion).
Timing: Prior to initiation of therapy.
Blood pressure (sitting and standing)
Rationale: To assess for baseline orthostatic hypotension and monitor for drug-induced hypotension.
Timing: Prior to initiation of therapy.
Complete Blood Count (CBC)
Rationale: To establish baseline and monitor for rare occurrences of hemolytic anemia or leukopenia.
Timing: Prior to initiation of therapy.
Liver function tests (LFTs)
Rationale: To establish baseline and monitor for rare hepatic enzyme elevations.
Timing: Prior to initiation of therapy.
Renal function (BUN, creatinine)
Rationale: To assess baseline kidney function, especially in elderly or renally impaired patients.
Timing: Prior to initiation of therapy.
Routine Monitoring
Motor function (dyskinesias, 'wearing-off', 'on-off' phenomena)
Frequency: Regularly, at each follow-up visit (e.g., every 3-6 months or as clinically indicated).
Target: Optimal symptom control with minimal dyskinesia.
Action Threshold: Worsening symptoms, new or increased dyskinesias, significant 'wearing-off' periods, or 'on-off' fluctuations require dose adjustment or addition of adjunctive therapy.
Mental status (hallucinations, confusion, impulse control disorders)
Frequency: Regularly, at each follow-up visit.
Target: Absence of significant psychiatric symptoms.
Action Threshold: New or worsening psychiatric symptoms require dose reduction or discontinuation.
Blood pressure (sitting and standing)
Frequency: Regularly, at each follow-up visit.
Target: Stable blood pressure, absence of symptomatic orthostatic hypotension.
Action Threshold: Symptomatic orthostatic hypotension requires dose adjustment or management strategies.
Complete Blood Count (CBC)
Frequency: Periodically (e.g., annually or as clinically indicated), especially if unexplained fatigue or pallor occurs.
Target: Within normal limits.
Action Threshold: Significant abnormalities (e.g., hemolytic anemia, leukopenia) require investigation and potential drug discontinuation.
Liver function tests (LFTs)
Frequency: Periodically (e.g., annually or as clinically indicated), especially if symptoms of liver dysfunction occur.
Target: Within normal limits.
Action Threshold: Significant elevations require investigation and potential drug discontinuation.
Symptom Monitoring
- Dyskinesias (involuntary movements)
- Nausea/vomiting
- Orthostatic hypotension (dizziness upon standing)
- Hallucinations
- Confusion
- Insomnia/sleep disturbances
- Impulse control disorders (e.g., pathological gambling, hypersexuality, compulsive shopping)
- 'Wearing-off' (return of symptoms before next dose)
- 'On-off' phenomena (unpredictable fluctuations between good and poor motor control)
- Dry mouth
- Darkening of urine, sweat, or saliva (harmless)
Special Patient Groups
Pregnancy
Category C. Use during pregnancy only if the potential benefit justifies the potential risk to the fetus. Levodopa has shown developmental toxicity in animal studies.
Trimester-Specific Risks:
First Trimester:
Potential for developmental toxicity observed in animal studies. Human data are limited.
Second Trimester:
Limited human data. Risk vs. benefit should be carefully weighed.
Third Trimester:
Limited human data. Risk vs. benefit should be carefully weighed. May affect uterine contractility.
Lactation
Levodopa is excreted into breast milk and may suppress lactation. Carbidopa's excretion into breast milk is unknown. Due to potential for serious adverse reactions in the infant, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Infant Risk:
L3 (Moderate risk). Potential for adverse effects in the infant (e.g., motor abnormalities, developmental effects). May suppress lactation.
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Generally not recommended for use in patients under 18 years of age.
Geriatric Use
No specific dose adjustment is typically required based on age alone, but elderly patients may be more sensitive to the central nervous system side effects (e.g., hallucinations, confusion, dyskinesias) and orthostatic hypotension. Start with lower doses and titrate slowly, monitoring closely for adverse effects.
Clinical Information
Clinical Pearls
- Carbidopa/levodopa is considered the most effective medication for the motor symptoms of Parkinson's disease, particularly bradykinesia and rigidity.
- The 'wearing-off' phenomenon (shortening of drug effect) and dyskinesias (involuntary movements) are common long-term complications, often requiring dose adjustments, more frequent dosing, or addition of adjunctive therapies.
- Protein redistribution: Advise patients to take the medication at least 30 minutes before or 1 hour after high-protein meals to optimize absorption and reduce 'off' times.
- Do not crush or chew extended-release formulations (e.g., Rytary). Standard tablets can be split if scored.
- Patients should be warned about the potential for sudden onset of sleep and impulse control disorders (e.g., pathological gambling, hypersexuality), which require careful monitoring and discussion with the physician.
- Abrupt discontinuation can lead to a neuroleptic malignant syndrome-like syndrome, characterized by fever, rigidity, altered mental status, and autonomic instability. Taper slowly if discontinuation is necessary.
Alternative Therapies
- Dopamine agonists (e.g., pramipexole, ropinirole, rotigotine)
- MAO-B inhibitors (e.g., selegiline, rasagiline, safinamide)
- COMT inhibitors (e.g., entacapone, opicapone, tolcapone)
- Amantadine (for dyskinesia or mild symptoms)
- Anticholinergics (e.g., benztropine, trihexyphenidyl - for tremor, less common due to side effects)
- Istradefylline (adenosine A2A receptor antagonist, for 'off' episodes)
Cost & Coverage
Average Cost:
Varies widely, typically $30-$150 per 30 tablets (25/250 mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (generic), Tier 3 or higher (brand/extended-release)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.