Carbidopa and levodopa 25 mg; 100 mg Tablet, 180-count
🆔 Identity & classification
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🏷️ RxNorm drug class
This medicine belongs to the Aromatic Amino Acid Decarboxylation Inhibitor class.
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🏭 Manufacturer & labeler
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🩺 Clinical
Levodopa and carbidopa is used to treat the symptoms of Parkinson's disease and Parkinson's-like symptoms that may develop after encephalitis (swelling of the brain) or injury to the nervous system caused by carbon monoxide poisoning or manganese poisoning. Levodopa is in a class of medications called central nervous system agents. It works by being converted to dopamine in the brain (the natural substance that is low in Parkinson's and causes the symptoms of tremor, stiffness, and slowness of movement). Carbidopa is in a class of medications called decarboxylase inhibitors. It works by preven...
Read the full MedlinePlus article ↗- Levodopa is the medicine that actually works in your brain — it crosses into the brain and gets converted into dopamine, the chemical that Parkinson's disease depletes. The problem...
- What exactly does levodopa and carbidopa do, and why do I need both?
- Generally yes, but the timing and content of your meals can matter. High-protein foods — like large servings of meat, eggs, or dairy — can compete with levodopa for absorption in y...
- Can I eat normally while taking this medication?
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
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UNII OP1R32D61U
Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
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UNII CQ3XH3DET6
D&C Yellow No. 10 Aluminum Lake is a yellow colorant made by combining a dye with aluminum salts. It's used in medicines to add color for product identification and visual appeal.
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UNII H77VEI93A8
A synthetic yellow dye used to color medications. It helps identify the drug and make it visually distinctive, with no effect on how the medicine works.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII O8232NY3SJ
A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.
5 inactive ingredients listed in the exact product block matched to this NDC.
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ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.1325 | $23.85 / 180 tablets |
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🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Carbidopa and levodopa 25 mg/1; 100 mg 00093-9702-01 | Teva | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 00904-7501-61 | Major | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 31722-0382-01 | Camber | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50228-0458-01 | ScieGen | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa-levodopa 25 mg/1; 100 mg 52817-0391-00 | TruPharma, | 1000 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 59651-0457-01 | Aurobindo | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 60687-0661-01 | American | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 69367-0339-01 | Westminster | 100 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa-levodopa 25 mg/1; 100 mg 72888-0107-00 | Advagen | 1000 tablets | $0.077 | AB | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 75907-0020-01 | Dr. | 100 tablets | $0.077 | AB | Availability likely | — |
| Sinemet 25 mg/1; 100 mg 78206-0168-01 | Organon | 100 tablets | $1.424 | AB | Discontinued | — |
| Sinemet 25 mg/1; 100 mg 78206-0190-01 | Organon | 100 tablets | $1.424 | AB | Availability likely | — |
| Dhivy 25 mg/1; 100 mg 75854-0701-01 | Avion | 100 tablets | $3.614 | — | Availability likely | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 00615-8536-05 | NCS | 15 tablets | — | AB | FDA listed | — |
| Carbidopa and levodopa 25 mg/1; 100 mg 42291-0472-01 | AvKARE | 100 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50090-5969-01 | A-S | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50090-6580-01 | A-S | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50090-6725-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and levodopa 25 mg/1; 100 mg 50090-6727-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50090-7498-01 | A-S | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50090-7499-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 50268-0202-15 | AvPAK | 50 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 55154-2643-00 | Cardinal | 10 tablets | — | AB | FDA listed | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 62756-0518-08 | Sun | 100 tablets | — | AB | FDA listed | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 63629-2356-01 | Bryant | 500 tablets | — | AB | Discontinued | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 63629-2357-01 | Bryant | 100 tablets | — | AB | Discontinued | — |
| Carbidopa-levodopa 25 mg/1; 100 mg 67046-1507-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 68071-2240-01 | NuCare | 100 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 71205-0878-00 | Proficient | 100 tablets | — | AB | FDA listed | — |
| Carbidopa-levodopa 25 mg/1; 100 mg 71335-2588-01 | Bryant | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and Levodopa 25 mg/1; 100 mg 71610-0647-60 | Aphena | 90 tablets | — | AB | FDA listed | — |
| Carbidopa and levodopa 25 mg/1; 100 mgthis 71610-0664-80 | Aphena | 180 tablets | — | AB | FDA listed | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 72865-0362-01 | XLCare | 100 tablets | — | AB | FDA listed | — |
| Carbidopa And Levodopa 25 mg/1; 100 mg 53401-0020-60 | Aphena | 90 tablets | — | AB | FDA listed | — |
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⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
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📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 71610-0664-60 | 90 TABLET in 1 BOTTLE (71610-664-60) | 2022-10-04 | Active |
| 71610-0664-80 You're viewing this | 180 TABLET in 1 BOTTLE (71610-664-80) | 2022-10-17 | Active |
You're viewing the largest of 2 pack sizes for this product.
Pack size FAQ
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🧭 About this NDC listing & data coverage
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| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
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📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS AND USAGE Carbidopa and levodopa tablets are indicated in the treatment of Parkinson's disease, post-encephalitic parkinsonism, and symptomatic parkinsonism that may follow carbon monoxide intoxication or manganese intoxication. Carbidopa allows patients treated for Parkinson's disease to use much lower doses of levodopa. Some patients who responded poorly to levodopa have improved on carbidopa and levodopa.
This is most likely due to decreased peripheral decarboxylation of levodopa caused by administration of carbidopa rather than by a primary effect of carbidopa on the nervous system. Carbidopa has not been shown to enhance the intrinsic efficacy of levodopa. Carbidopa may also reduce nausea and vomiting and permit more rapid titration of levodopa.
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION The optimum daily dosage of carbidopa and levodopa must be determined by careful titration in each patient. Carbidopa and levodopa tablets are available in a 1:4 ratio of carbidopa to levodopa (25 mg/100 mg) as well as 1:10 ratio (25 mg/250 mg and 10 mg/100 mg). Tablets of the two ratios may be given separately or combined as needed to provide the optimum dosage.
Studies show that peripheral dopa decarboxylase is saturated by carbidopa at approximately 70 to 100 mg a day. Patients receiving less than this amount of carbidopa are more likely to experience nausea and vomiting. Usual Initial Dosage Dosage is best initiated with one tablet of carbidopa and levodopa 25 mg/100 mg three times a day.
This dosage schedule provides 75 mg of carbidopa per day. Dosage may be increased by one tablet every day or every other day, as necessary, until a dosage of eight tablets of carbidopa and levodopa 25 mg/100 mg a day is reached. If carbidopa and levodopa 10 mg/100 mg is used, dosage may be initiated with one tablet three or four times a day.
However, this will not provide an adequate amount of carbidopa for many patients. Dosage may be increased by one tablet every day or every other day until a total of eight tablets (2 tablets four times a day) is reached. How to Transfer Patients from Levodopa Levodopa must be discontinued at least twelve hours before starting this combination product.
A daily dosage of carbidopa and levodopa should be chosen that will provide approximately 25% of the previous levodopa dosage. Patients who are taking less than 1,500 mg of levodopa a day should be started on one tablet of carbidopa and levodopa 25 mg/100 mg three or four times a day. The suggested starting dosage for most patients taking more than 1,500 mg of levodopa is one tablet of carbidopa and levodopa 25 mg/250 mg three or four times a day.
Maintenance Therapy should be individualized and adjusted according to the desired therapeutic response. At least 70 to 100 mg of carbidopa per day should be provided. When a greater proportion of carbidopa is required, one 25 mg/100 mg tablet may be substituted for each 10 mg/100 mg tablet.
When more levodopa is required, each 25 mg/250 mg tablet should be substituted for a 25 mg/100 mg tablet or a 10 mg/100 mg tablet. If necessary, the dosage of carbidopa and levodopa 25 mg/250 mg may be increased by one-half or one tablet every day or every other day to a maximum of eight tablets a day. Experience with total daily dosages of carbidopa greater than 200 mg is limited.
Because both therapeutic and adverse responses occur more rapidly with this combination product than with levodopa alone, patients should be monitored closely during the dose adjustment period. Specifically, involuntary movements will occur more rapidly with carbidopa and levodopa than with levodopa. The occurrence of involuntary movements may require dosage reduction.
Blepharospasm may be a useful early sign of excess dosage in some patients. Addition of Other Antiparkinsonian Medications Standard drugs for Parkinson's disease, other than levodopa without a decarboxylase inhibitor, may be used concomitantly while carbidopa and levodopa is being administered, although dosage adjustments may be required. Interruption of Therapy Sporadic cases of hyperpyrexia and confusion have been associated with dose reductions and withdrawal of carbidopa and levodopa.
Patients should be observed carefully if abrupt reduction or discontinuation of carbidopa and levodopa is required, especially if the patient is receiving neuroleptics (see WARNINGS ). If general anesthesia is required, carbidopa and levodopa may be continued as long as the patient is permitted to take fluids and medication by mouth. If therapy is interrupted temporarily, the patient should be observed for symptoms resembling NMS, and the usual daily dosage may be administered as soon as the patient is able to take oral medication.
⛔ Contraindications ▾
CONTRAINDICATIONS Nonselective monoamine oxidase (MAO) inhibitors are contraindicated for use with carbidopa and levodopa. These inhibitors must be discontinued at least two weeks prior to initiating therapy with this combination product. Carbidopa and levodopa may be administered concomitantly with the manufacturer's recommended dose of an MAO inhibitor with selectivity for MAO type B (e.g., selegiline HCl) (see PRECAUTIONS , Drug Interactions ).
Carbidopa and levodopa is contraindicated in patients with known hypersensitivity to any component of this drug, and in patients with narrow-angle glaucoma.
⚠️ Warnings ▾
WARNINGS When carbidopa and levodopa tablets are to be given to patients who are being treated with levodopa, levodopa must be discontinued at least twelve hours before therapy with the combination product is started. In order to reduce adverse reactions, it is necessary to individualize therapy. See DOSAGE AND ADMINISTRATION section before initiating therapy.
The addition of carbidopa with levodopa in the form of this combination product reduces the peripheral effects (nausea, vomiting) due to decarboxylation of levodopa; however, carbidopa does not decrease the adverse reactions due to the central effects of levodopa. Because carbidopa permits more levodopa to reach the brain and more dopamine to be formed, certain adverse central nervous system (CNS) effects, e.g., dyskinesias (involuntary movements), may occur at lower dosages and sooner with carbidopa and levodopa than with levodopa alone.
All patients should be observed carefully for the development of depression with concomitant suicidal tendencies. Carbidopa and levodopa should be administered cautiously to patients with severe cardiovascular or pulmonary disease, bronchial asthma, renal, hepatic or endocrine disease. As with levodopa, care should be exercised in administering the combination product, to patients with a history of myocardial infarction who have residual atrial, nodal, or ventricular arrhythmias.
In such patients, cardiac function should be monitored with particular care during the period of initial dosage adjustment, in a facility with provisions for intensive cardiac care. As with levodopa, treatment with the combination product may increase the possibility of upper gastrointestinal hemorrhage in patients with a history of peptic ulcer. Falling Asleep During Activities of Daily Living and Somnolence Patients taking carbidopa and levodopa alone or with other dopaminergic drugs have reported suddenly falling asleep without prior warning of sleepiness while engaged in activities of daily living (includes operation of motor vehicles).
Road traffic accidents attributed to sudden sleep onset have been reported. Although many patients reported somnolence while on dopaminergic medications, there have been reports of road traffic accidents attributed to sudden onset of sleep in which the patient did not perceive any warning signs, such as excessive drowsiness, and believed that they were alert immediately prior to the event. Sudden onset of sleep has been reported to occur as long as one year after the initiation of treatment.
Falling asleep while engaged in activities of daily living usually occurs in patients experiencing preexisting somnolence, although some patients may not give such a history. For this reason, prescribers should reassess patients for drowsiness or sleepiness especially since some of the events occur well after the start of treatment. Prescribers should be aware that patients may not acknowledge drowsiness or sleepiness until directly questioned about drowsiness or sleepiness during specific activities.
Patients should be advised to exercise caution while driving or operating machines during treatment with carbidopa and levodopa. Patients who have already experienced somnolence or an episode of sudden sleep onset should not participate in these activities during treatment with carbidopa and levodopa. Before initiating treatment with carbidopa and levodopa, advise patients about the potential to develop drowsiness and ask specifically about factors that may increase the risk for somnolence with carbidopa and levodopa such as the use of concomitant sedating medications and the presence of sleep disorders.
Consider discontinuing carbidopa and levodopa in patients who report significant daytime sleepiness or episodes of falling asleep during activities that require active participation (e.g., conversations, eating, etc.). If treatment with carbidopa and levodopa continues, patients should be advised not to drive and to avoid other potentially…
🤒 Adverse Reactions ▾
ADVERSE REACTIONS The most common adverse reactions reported with carbidopa and levodopa have included dyskinesias, such as choreiform, dystonic, and other involuntary movements, and nausea. The following other adverse reactions have been reported with carbidopa and levodopa: Body as a Whole Chest pain, asthenia. Cardiovascular Cardiac irregularities, hypotension, orthostatic effects including orthostatic hypotension, hypertension, syncope, phlebitis, palpitation.
Gastrointestinal Dark saliva, gastrointestinal bleeding, development of duodenal ulcer, anorexia, vomiting, diarrhea, constipation, dyspepsia, dry mouth, taste alterations. Hematologic Agranulocytosis, hemolytic and non-hemolytic anemia, thrombocytopenia, leukopenia. Hypersensitivity Angioedema, urticaria, pruritus, Henoch-Schönlein purpura, bullous lesions (including pemphigus-like reactions).
Musculoskeletal Back pain, shoulder pain, muscle cramps. Nervous System/Psychiatric Psychotic episodes including delusions, hallucinations, and paranoid ideation, bradykinetic episodes ("on-off" phenomenon), confusion, agitation, dizziness, somnolence, dream abnormalities including nightmares, insomnia, paresthesia, headache, depression with or without development of suicidal tendencies, dementia, pathological gambling, increased libido including hypersexuality, impulse control symptoms. Convulsions also have occurred; however, a causal relationship with carbidopa and levodopa has not been established.
Respiratory Dyspnea, upper respiratory infection. Skin Rash, increased sweating, alopecia, dark sweat. Urogenital Urinary tract infection, urinary frequency, dark urine.
Laboratory Tests Decreased hemoglobin and hematocrit; abnormalities in alkaline phosphatase, SGOT (AST), SGPT (ALT), LDH, bilirubin, BUN, Coombs test; elevated serum glucose; white blood cells, bacteria, and blood in the urine. Other adverse reactions that have been reported with levodopa alone and with various carbidopa and levodopa formulations, and may occur with this combination product are: Body as a Whole Abdominal pain and distress, fatigue. Cardiovascular Myocardial infarction.
Gastrointestinal Gastrointestinal pain, dysphagia, sialorrhea, flatulence, bruxism, burning sensation of the tongue, heartburn, hiccups. Metabolic Edema, weight gain, weight loss. Musculoskeletal Leg pain.
Nervous System/Psychiatric Ataxia, extrapyramidal disorder, falling, anxiety, gait abnormalities, nervousness, decreased mental acuity, memory impairment, disorientation, euphoria, blepharospasm (which may be taken as an early sign of excess dosage; consideration of dosage reduction may be made at this time), trismus, increased tremor, numbness, muscle twitching, activation of latent Horner's syndrome, peripheral neuropathy. Respiratory Pharyngeal pain, cough. Skin Malignant melanoma, flushing.
Special Senses Oculogyric crises, diplopia, blurred vision, dilated pupils. Urogenital Urinary retention, urinary incontinence, priapism. Miscellaneous Bizarre breathing patterns, faintness, hoarseness, malaise, hot flashes, sense of stimulation.
Laboratory Tests Decreased white blood cell count and serum potassium; increased serum creatinine and uric acid; protein and glucose in urine. To report SUSPECTED ADVERSE EVENTS, contact AvKARE at 1-855-361-3993 or FDA at 1-800-FDA-1088 or http://www.fda.gov/medwatch for voluntary reporting of adverse reactions.
🆘 Overdosage ▾
OVERDOSAGE Management of acute overdosage with carbidopa and levodopa is the same as management of acute overdosage with levodopa. Pyridoxine is not effective in reversing the actions of this product. General supportive measures should be employed, along with immediate gastric lavage.
Intravenous fluids should be administered judiciously and an adequate airway maintained. Electrocardiographic monitoring should be instituted and the patient carefully observed for the development of arrhythmias; if required, appropriate antiarrhythmic therapy should be given. The possibility that the patient may have taken other drugs as well as carbidopa and levodopa tablets should be taken into consideration.
To date, no experience has been reported with dialysis; hence, its value in overdosage is not known. Based on studies in which high doses of levodopa and/or carbidopa were administered, a significant proportion of rats and mice given single oral doses of levodopa of approximately 1,500 to 2,000 mg/kg are expected to die. A significant proportion of infant rats of both sexes are expected to die at a dose of 800 mg/kg.
A significant proportion of rats are expected to die after treatment with similar doses of carbidopa. The addition of carbidopa in a 1:10 ratio with levodopa increases the dose at which a significant proportion of mice are expected to die to 3,360 mg/kg.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Mechanism of Action Parkinson's disease is a progressive, neurodegenerative disorder of the extrapyramidal nervous system affecting the mobility and control of the skeletal muscular system. Its characteristic features include resting tremor, rigidity, and bradykinetic movements. Symptomatic treatments, such as levodopa therapies, may permit the patient better mobility.
Current evidence indicates that symptoms of Parkinson's disease are related to depletion of dopamine in the corpus striatum. Administration of dopamine is ineffective in the treatment of Parkinson's disease apparently because it does not cross the blood-brain barrier. However, levodopa, the metabolic precursor of dopamine, does cross the blood-brain barrier, and presumably is converted to dopamine in the brain.
This is thought to be the mechanism whereby levodopa relieves symptoms of Parkinson's disease. Pharmacodynamics When levodopa is administered orally, it is rapidly decarboxylated to dopamine in extracerebral tissues so that only a small portion of a given dose is transported unchanged to the central nervous system. For this reason, large doses of levodopa are required for adequate therapeutic effect, and these may often be accompanied by nausea and other adverse reactions, some of which are attributable to dopamine formed in extracerebral tissues.
Since levodopa competes with certain amino acids for transport across the gut wall, the absorption of levodopa may be impaired in some patients on a high protein diet. Carbidopa inhibits decarboxylation of peripheral levodopa. It does not cross the blood-brain barrier and does not affect the metabolism of levodopa within the central nervous system.
The incidence of levodopa-induced nausea and vomiting is less with the combination product than with levodopa. In many patients, this reduction in nausea and vomiting will permit more rapid dosage titration. Since its decarboxylase inhibiting activity is limited to extracerebral tissues, administration of carbidopa with levodopa makes more levodopa available for transport to the brain.
Pharmacokinetics Carbidopa reduces the amount of levodopa required to produce a given response by about 75% and, when administered with levodopa, increases both plasma levels and the plasma half-life of levodopa, and decreases plasma and urinary dopamine and homovanillic acid. The plasma half-life of levodopa is about 50 minutes, without carbidopa. When carbidopa and levodopa are administered together, the half-life of levodopa is increased to about 1.5 hours.
At steady state, the bioavailability of carbidopa from carbidopa and levodopa tablets is approximately 99% relative to the concomitant administration of carbidopa and levodopa. In clinical pharmacologic studies, simultaneous administration of carbidopa and levodopa produced greater urinary excretion of levodopa in proportion to the excretion of dopamine than administration of the two drugs at separate times. Pyridoxine hydrochloride (vitamin B 6 ), in oral doses of 10 mg to 25 mg, may reverse the effects of levodopa by increasing the rate of aromatic amino acid decarboxylation.
Carbidopa inhibits this action of pyridoxine; therefore, carbidopa and levodopa can be given to patients receiving supplemental pyridoxine (vitamin B 6 ). Special Populations Geriatric: A study in eight young healthy subjects (21 to 22 yr) and eight elderly healthy subjects (69 to 76 yr) showed that the absolute bioavailability of levodopa was similar between young and elderly subjects following oral administration of levodopa and carbidopa. However, the systemic exposure (AUC) of levodopa was increased by 55% in elderly subjects compared to young subjects.
Based on another study in forty patients with Parkinson’s disease, there was a correlation between age of patients and the increase of AUC of levodopa following administration of levodopa and an inhibitor of peripheral dopa decarboxylase. AUC of levodopa was increased by 28% in elde…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Carbidopa and Levodopa Tablets, USP are supplied as follows: 10 mg/100 mg — Each dark blue, mottled, round tablet imprinted with ‘TV’ on one side and ‘9701’on the other side contains 10 mg of carbidopa, USP and 100 mg of levodopa, USP. 25 mg/100 mg — Each yellow, mottled, round tablet imprinted with ‘TV’ on one side and ‘9702’on the other side contains 25 mg of carbidopa, USP and 100 mg of levodopa, USP and is supplied in bottles of 100 (NDC 42291-472-01) and 1000 (NDC 42291-472-10). 25 mg/250 mg — Each light blue, mottled, round tablet imprinted with ‘TV’ on one side and ‘9703’ on the other side contains 25 mg of carbidopa, USP and 250 mg of levodopa, USP .
Store at 25ºC (77ºF); excursions permitted to 15º to 30ºC (59º to 86ºF) [see USP Controlled Room Temperature]. Protect from light. Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure (as required).
Manufactured for: AvKARE Pulaski, TN 38478 Mfg. Rev. B 09/20 AV 03/21 (P)
📋 Description ▾
DESCRIPTION Carbidopa and levodopa tablets, USP are a combination product for the treatment of Parkinson's disease and syndrome. Carbidopa, USP an inhibitor of aromatic amino acid decarboxylation, is a white, crystalline compound, slightly soluble in water, with a molecular weight of 244.24. It is designated chemically as (-)-L-α-hydrazino-α-methyl-β-(3,4-dihydroxybenzene) propanoic acid monohydrate.
Its molecular formula is C 10 H 14 N 2 O 4 •H 2 O, and its structural formula is: Tablet content is expressed in terms of anhydrous carbidopa which has a molecular weight of 226.23. Levodopa, USP an aromatic amino acid, is a white, crystalline compound, slightly soluble in water, with a molecular weight of 197.19. It is designated chemically as (-)-L-α-amino-β-(3,4-dihydroxybenzene) propanoic acid.
Its molecular formula is C 9 H 11 NO 4 , and its structural formula is: Carbidopa and Levodopa Tablets, USP for oral administration, are supplied in three strengths: 10 mg/100 mg, containing 10 mg of carbidopa, USP and 100 mg of levodopa, USP. 25 mg/100 mg, containing 25 mg of carbidopa, USP and 100 mg of levodopa, USP. 25 mg/250 mg, containing 25 mg of carbidopa, USP and 250 mg of levodopa, USP.
In addition, each tablet contains the following inactive ingredients: corn starch, magnesium stearate, microcrystalline cellulose, pregelatinized starch (maize). In addition, the 25 mg/100 mg strength contain D&C yellow #10 aluminum lake and FD&C yellow #6 aluminum lake (sunset yellow lake). The 10 mg/100 mg and 25 mg/250 mg strengths contain FD&C blue #2 aluminum lake.
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