Carbidopa/levod 25-100mg Scored T
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-Parkinson agent
Pharmacologic Class
Dopamine precursor; DOPA decarboxylase inhibitor
Pregnancy Category
C
FDA Approved
Jun 1975
DEA Schedule
Not Controlled
Overview
What is this medicine?
This medication is used to treat Parkinson's disease. It works by increasing the amount of a natural substance called dopamine in your brain, which helps to improve movement, reduce stiffness, and control tremors. Carbidopa helps levodopa (the main active ingredient) get to your brain more effectively and reduces side effects.
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.
Some tablets may have a score line, which allows you to split them if needed. However, only split the tablets on the score line. 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, as iron may reduce the absorption of this drug.
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 decrease absorption. Discuss your diet with your doctor, especially if you plan to make any changes.
Continue taking this medication even when you're 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're feeling well.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Do not store it in a bathroom. Keep all medications in a safe place, out of the reach of children and pets.
When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, check with your pharmacist for guidance on the best disposal method. You may also want to explore 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 make up for a missed one.
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.
Some tablets may have a score line, which allows you to split them if needed. However, only split the tablets on the score line. 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, as iron may reduce the absorption of this drug.
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 decrease absorption. Discuss your diet with your doctor, especially if you plan to make any changes.
Continue taking this medication even when you're 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're feeling well.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Do not store it in a bathroom. Keep all medications in a safe place, out of the reach of children and pets.
When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, check with your pharmacist for guidance on the best disposal method. You may also want to explore 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 make up for a missed one.
Lifestyle & Tips
- Take this medication exactly as prescribed by your doctor. Do not stop taking it suddenly without consulting your doctor, as this can lead to serious side effects.
- Take with food if stomach upset occurs, but avoid high-protein meals (meat, dairy, nuts) around the time you take your dose, as protein can interfere with absorption. Discuss timing with your doctor or pharmacist.
- Do not crush or chew extended-release tablets; swallow them whole. Scored tablets can be broken if needed for dosing.
- Stand up slowly from a sitting or lying position to avoid dizziness or lightheadedness (orthostatic hypotension).
- Report any new or worsening involuntary movements (dyskinesias), hallucinations, confusion, or unusual urges (e.g., gambling, shopping) to your doctor immediately.
- Urine, sweat, or saliva may turn dark red, brown, or black. This is a harmless side effect due to the medication.
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: 25 mg carbidopa/100 mg levodopa three times daily. Titrate as needed.
Dose Range:
75 - 800 mg
Condition-Specific Dosing:
Parkinson's Disease (initial):
25 mg carbidopa/100 mg levodopa three times daily. May increase by 1 tablet every 1-2 days until optimal response is achieved. Max: 8 tablets/day (200 mg carbidopa/800 mg levodopa).
Parkinson's Disease (conversion from levodopa):
Approximately 25% of previous levodopa dose. Carbidopa should be at least 70-100 mg/day to inhibit peripheral decarboxylation.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed
Moderate:
No specific adjustment needed
Severe:
Use with caution; monitor for adverse effects. Levodopa is not significantly cleared by dialysis.
Dialysis:
Not significantly dialyzable; no supplemental dose needed post-dialysis. Monitor for adverse effects.
Hepatic Impairment:
Mild:
No specific adjustment needed
Moderate:
No specific adjustment needed
Severe:
Use with caution; monitor for adverse effects.
Confidence:
Medium
Pharmacology
Mechanism of Action
Carbidopa inhibits peripheral DOPA decarboxylase, an enzyme that metabolizes levodopa to dopamine in the periphery. This allows a greater proportion of 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, and its conversion to dopamine in the brain helps to replenish dopamine stores in patients with Parkinson's disease, who have a deficiency of dopamine in the substantia nigra.
Pharmacokinetics
Absorption:
Bioavailability:
Levodopa: 30% (without carbidopa), 70-80% (with carbidopa). Carbidopa: 40-70%.
Tmax:
Levodopa: 0.5-2 hours (immediate release). Carbidopa: 1.5-2 hours.
FoodEffect:
High-protein meals can reduce levodopa absorption and transport across the BBB due to competition for amino acid transporters. Food generally delays Tmax and decreases Cmax.
Distribution:
Vd:
Levodopa: 0.9-1.6 L/kg. Carbidopa: 1.1 L/kg.
ProteinBinding:
Levodopa: Low (10-30%). Carbidopa: Approximately 36%.
CnssPenetration:
Levodopa: Yes (requires active transport). Carbidopa: Limited (does not cross BBB significantly).
Elimination:
HalfLife:
Levodopa: 1-2 hours (with carbidopa). Carbidopa: Approximately 2-3 hours.
Clearance:
Levodopa: 0.3 L/kg/hr.
ExcretionRoute:
Renal (primarily as metabolites)
Unchanged:
Levodopa: <1% (with carbidopa). Carbidopa: 30% (unchanged in urine).
Pharmacodynamics
OnsetOfAction:
Within 30 minutes to 1 hour (for motor symptoms, after initial dose). Full therapeutic effect may take weeks of titration.
PeakEffect:
1-2 hours after dose.
DurationOfAction:
Approximately 4-6 hours (immediate release), highly variable among patients.
Confidence:
Medium
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 experience 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
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Passing out
+ Changes in eyesight
New or worsening behavioral or mood changes, such as:
+ Depression
+ Thoughts of suicide
Hallucinations (seeing or hearing things that are not there)
Feeling confused
Strong, uncontrollable urges (e.g., eating, gambling, sex, or spending money)
A skin lump or growth
Changes in the color or size of a mole
New or worsening trouble controlling body movements
Eyelid twitching
Muscle twitching
Stomach pain
Black, tarry, or bloody stools
Vomiting blood or material that looks like coffee grounds
Chest pain or pressure
Fast or abnormal heartbeat
Fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Dark urine or yellow skin and eyes
Changes in eyesight, eye pain, or severe eye irritation
Shortness of breath
Some people have experienced sudden sleepiness during activities like driving, eating, or talking, even if they felt alert beforehand. 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 sudden sleepiness or excessive sleepiness.
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people do not experience side effects or only have mild ones. If you experience any of the following side effects or any other side effects that bother you or do not go away, contact your doctor:
Bad dreams
Constipation
Dizziness or sleepiness
Dry mouth
Headache
Trouble sleeping
Some products may cause a dark red, brown, or black color to appear in your saliva, urine, or sweat, which is harmless but may discolor your clothes
Upset stomach or vomiting
This is not a comprehensive list of all possible side effects. If you have questions or concerns about side effects, 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 experience 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
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Passing out
+ Changes in eyesight
New or worsening behavioral or mood changes, such as:
+ Depression
+ Thoughts of suicide
Hallucinations (seeing or hearing things that are not there)
Feeling confused
Strong, uncontrollable urges (e.g., eating, gambling, sex, or spending money)
A skin lump or growth
Changes in the color or size of a mole
New or worsening trouble controlling body movements
Eyelid twitching
Muscle twitching
Stomach pain
Black, tarry, or bloody stools
Vomiting blood or material that looks like coffee grounds
Chest pain or pressure
Fast or abnormal heartbeat
Fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Dark urine or yellow skin and eyes
Changes in eyesight, eye pain, or severe eye irritation
Shortness of breath
Some people have experienced sudden sleepiness during activities like driving, eating, or talking, even if they felt alert beforehand. 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 sudden sleepiness or excessive sleepiness.
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people do not experience side effects or only have mild ones. If you experience any of the following side effects or any other side effects that bother you or do not go away, contact your doctor:
Bad dreams
Constipation
Dizziness or sleepiness
Dry mouth
Headache
Trouble sleeping
Some products may cause a dark red, brown, or black color to appear in your saliva, urine, or sweat, which is harmless but may discolor your clothes
Upset stomach or vomiting
This is not a comprehensive list of all possible side effects. If you have questions or concerns about side effects, 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, jerky movements (dyskinesias)
- Hallucinations (seeing or hearing things that are not there)
- Confusion, disorientation, or unusual thoughts
- Unusual urges or behaviors (e.g., compulsive gambling, hypersexuality, binge eating)
- Severe nausea or vomiting that does not subside
- Muscle stiffness or rigidity that worsens suddenly (may indicate neuroleptic malignant syndrome-like reaction if medication is 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, such as foods or drugs. Be sure to describe the allergic reaction you experienced.
Certain health conditions, including:
+ Glaucoma
+ Skin lumps or growths
+ A history of skin cancer
Current or recent use of specific medications, such as:
+ Reserpine or tetrabenazine
+ Linezolid or methylene blue
+ Certain antidepressants or Parkinson's disease medications taken within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline (as this may increase the risk of very high blood pressure)
Use of any other medication that contains the same active ingredient as this drug
* All your prescription and over-the-counter medications, natural products, vitamins, and health problems, as this is not an exhaustive list of potential interactions
To ensure your safety, it is crucial to consult with your doctor and pharmacist about all your medications and health conditions before taking this drug. Do not start, stop, or change the dose of any medication without first discussing it 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, such as foods or drugs. Be sure to describe the allergic reaction you experienced.
Certain health conditions, including:
+ Glaucoma
+ Skin lumps or growths
+ A history of skin cancer
Current or recent use of specific medications, such as:
+ Reserpine or tetrabenazine
+ Linezolid or methylene blue
+ Certain antidepressants or Parkinson's disease medications taken within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline (as this may increase the risk of very high blood pressure)
Use of any other medication that contains the same active ingredient as this drug
* All your prescription and over-the-counter medications, natural products, vitamins, and health problems, as this is not an exhaustive list of potential interactions
To ensure your safety, it is crucial to consult with your doctor and pharmacist about all your medications and health conditions before taking this drug. Do not start, stop, or change the dose of any medication without first discussing it with your doctor.
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 your doctor about the most suitable glucose tests to use, as this medication may affect the results. You may experience a decrease in the medication's effectiveness as the time for your next dose approaches, which is known as "wearing off." If this occurs and bothers you, discuss it with your doctor.
Before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may cause drowsiness, consult your doctor. It is also important to note that people with Parkinson's disease may have a higher risk of developing a type of skin cancer called melanoma, although it is unclear if this medication contributes to this risk. Regular skin exams are recommended, and you should discuss any concerns with your doctor.
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, changes in thinking, abnormal heartbeat, or excessive sweating. If you experience any of these symptoms, contact your doctor immediately.
If you are pregnant, plan to become pregnant, or are breastfeeding, inform your doctor, as they will need to discuss the potential benefits and risks of this medication to 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 your doctor about the most suitable glucose tests to use, as this medication may affect the results. You may experience a decrease in the medication's effectiveness as the time for your next dose approaches, which is known as "wearing off." If this occurs and bothers you, discuss it with your doctor.
Before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may cause drowsiness, consult your doctor. It is also important to note that people with Parkinson's disease may have a higher risk of developing a type of skin cancer called melanoma, although it is unclear if this medication contributes to this risk. Regular skin exams are recommended, and you should discuss any concerns with your doctor.
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, changes in thinking, abnormal heartbeat, or excessive sweating. If you experience any of these symptoms, contact your doctor immediately.
If you are pregnant, plan to become pregnant, or are breastfeeding, inform your doctor, as they will need to discuss the potential benefits and risks of this medication to you and your baby.
Overdose Information
Overdose Symptoms:
- Severe involuntary movements (dyskinesias)
- Severe nausea and vomiting
- Cardiac arrhythmias (irregular heartbeat)
- Orthostatic hypotension
- Confusion, agitation, psychosis
- Blepharospasm (involuntary eyelid closure)
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Management is supportive, including gastric lavage, IV fluids, and antiarrhythmics if needed. Monitor cardiac function and vital signs.
Drug Interactions
Contraindicated Interactions
- Nonselective Monoamine Oxidase Inhibitors (MAOIs) (e.g., phenelzine, tranylcypromine): Risk of hypertensive crisis. Discontinue MAOIs at least 2 weeks prior to starting carbidopa/levodopa.
Major Interactions
- Antipsychotics (e.g., haloperidol, chlorpromazine, risperidone, olanzapine): May antagonize the effects of levodopa due to dopamine receptor blockade, worsening Parkinson's symptoms. Atypical antipsychotics (e.g., clozapine, quetiapine) may be less problematic.
- Iron salts (ferrous sulfate, gluconate): May chelate levodopa, reducing its absorption. Separate administration by at least 2 hours.
- Metoclopramide: May antagonize the effects of levodopa and increase risk of extrapyramidal symptoms.
- Pyridoxine (Vitamin B6) in high doses (>10-25 mg): Can reverse the effects of levodopa by increasing peripheral DOPA decarboxylase activity (less relevant with carbidopa co-administration, but still cautioned).
Moderate Interactions
- Antihypertensives: May cause additive hypotensive effects, especially orthostatic hypotension.
- Tricyclic Antidepressants (TCAs): May increase risk of orthostatic hypotension and hypertension. Use with caution.
- Sympathomimetics (e.g., epinephrine, norepinephrine, dopamine): May increase risk of cardiac arrhythmias. Monitor cardiac function.
- Protein-rich foods: Can reduce levodopa absorption and transport to the brain due to competition for amino acid transporters. Advise patients to take medication 30-60 minutes before or 1-2 hours after high-protein meals.
Minor Interactions
- Antacids: May increase levodopa absorption slightly.
Monitoring
Baseline Monitoring
Motor function (UPDRS, Hoehn & Yahr scale)
Rationale: To establish baseline severity of Parkinson's symptoms and assess therapeutic response.
Timing: Prior to initiation
Mental status/Cognitive function
Rationale: To assess baseline cognitive status and monitor for drug-induced psychiatric side effects (e.g., hallucinations, confusion).
Timing: Prior to initiation
Blood pressure (supine and standing)
Rationale: To establish baseline and monitor for orthostatic hypotension.
Timing: Prior to initiation
Renal and hepatic function tests
Rationale: To assess baseline organ function, although dose adjustments are not typically required for mild-moderate impairment.
Timing: Prior to initiation
Routine Monitoring
Motor function (e.g., tremor, rigidity, bradykinesia, gait)
Frequency: Regularly during titration and at follow-up visits (e.g., every 3-6 months or as clinically indicated)
Target: Improvement in symptoms with minimal dyskinesia
Action Threshold: Worsening symptoms, new or worsening dyskinesias, 'wearing off' phenomena, or 'on-off' fluctuations indicate need for dose adjustment or adjunctive therapy.
Dyskinesias (involuntary movements)
Frequency: At each visit, especially during dose titration
Target: Absence or minimal dyskinesias
Action Threshold: Presence of bothersome dyskinesias may require dose reduction or adjustment of dosing frequency.
Mental status (e.g., hallucinations, delusions, confusion, impulse control disorders)
Frequency: At each visit
Target: Normal cognitive function and behavior
Action Threshold: New or worsening psychiatric symptoms require dose reduction or consideration of alternative therapies.
Blood pressure (supine and standing)
Frequency: Regularly, especially during dose titration and if symptoms of orthostatic hypotension occur
Target: Stable blood pressure, no symptomatic orthostatic hypotension
Action Threshold: Symptomatic orthostatic hypotension (e.g., dizziness, syncope) requires intervention (e.g., dose reduction, non-pharmacological measures).
Intraocular pressure (in patients with glaucoma)
Frequency: Periodically
Target: Stable intraocular pressure
Action Threshold: Significant increase in intraocular pressure may necessitate re-evaluation of therapy.
Symptom Monitoring
- Orthostatic hypotension (dizziness, lightheadedness upon standing)
- Nausea/vomiting
- Dyskinesias (involuntary, uncontrolled movements)
- Hallucinations, delusions, confusion, psychosis
- Sleep disturbances (insomnia, somnolence, vivid dreams)
- Impulse control disorders (e.g., pathological gambling, hypersexuality, compulsive shopping, binge eating)
- 'Wearing off' phenomena (return of symptoms before next dose)
- 'On-off' fluctuations (abrupt, unpredictable changes between good and poor motor control)
- Depression, anxiety
- Darkening of urine, sweat, or saliva (harmless, due to levodopa 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. There are no adequate and well-controlled studies in pregnant women.
Trimester-Specific Risks:
First Trimester:
Potential for teratogenicity observed in animal studies at high doses. Human data are limited.
Second Trimester:
Limited human data. Risk of adverse effects on fetal development is not well established.
Third Trimester:
Limited human data. Risk of adverse effects on fetal development is not well established. Consider potential for premature labor or other complications.
Lactation
Levodopa is excreted into breast milk. Carbidopa is also likely excreted. Due to the potential for serious adverse reactions in breastfed infants (e.g., suppression of lactation, effects on CNS, motor development), 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 (Moderately safe). Potential for CNS effects (dyskinesias, sedation), endocrine effects (inhibition of prolactin), and nutritional effects (competition with amino acids). Monitor infant for irritability, poor feeding, or unusual movements.
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Carbidopa/levodopa is generally not indicated for use in children, as Parkinson's disease is rare in this population. Juvenile Parkinsonism is treated on a case-by-case basis, often with similar agents but with careful monitoring.
Geriatric Use
Elderly patients may be more sensitive to the central nervous system side effects (e.g., hallucinations, confusion, dyskinesias) and orthostatic hypotensive effects of carbidopa/levodopa. Initiate therapy with lower doses and titrate slowly. Monitor closely for adverse effects.
Clinical Information
Clinical Pearls
- Carbidopa/levodopa is the most effective medication for the motor symptoms of Parkinson's disease, particularly bradykinesia and rigidity.
- The 'wearing off' phenomenon (return of symptoms before the next dose) and 'on-off' fluctuations (unpredictable shifts between good and poor motor control) are common complications with long-term use. Strategies include more frequent dosing, extended-release formulations, or adjunctive therapies.
- High-protein meals can significantly reduce levodopa absorption and efficacy. Advise patients to take medication 30-60 minutes before or 1-2 hours after protein-rich meals, or to distribute protein intake throughout the day.
- Impulse control disorders (e.g., pathological gambling, hypersexuality, compulsive shopping, binge eating) can occur, especially with higher doses. Patients and caregivers should be counselled on this potential side effect.
- Abrupt discontinuation or rapid dose reduction can lead to a neuroleptic malignant syndrome-like reaction (fever, rigidity, altered mental status, autonomic instability), which can be life-threatening. Taper off slowly if discontinuation is necessary.
- Darkening of urine, sweat, or saliva is a harmless side effect due to levodopa metabolites and should not cause alarm.
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 and motor fluctuations)
- Istradefylline (adenosine A2A receptor antagonist, for 'off' episodes)
- Pimavanserin (for Parkinson's disease psychosis)
- Deep Brain Stimulation (DBS) surgery (for advanced Parkinson's disease with motor fluctuations and dyskinesias)
Cost & Coverage
Average Cost:
$20 - $100 per 30 tablets (generic 25-100mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (most insurance plans cover generic forms)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. It's also important to note that some medications may come with additional patient information leaflets, so be sure to check with your pharmacist for more details. 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 for clarification. 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 information about the medication taken, the amount, and the time it occurred, as this will aid in providing you with the most effective care.