Carbidopa, Levodopa And Entacapone

FDA Drug Information • Also known as: Carbidopa, Levodopa And Entacapone, Carbidopa, Levodopa, And Entacapone

Brand Names: Carbidopa, Levodopa And Entacapone, Carbidopa, Levodopa, And Entacapone
Drug Class: Aromatic Amino Acid [EPC], Catechol-O-Methyltransferase Inhibitor [EPC], Aromatic Amino Acid Decarboxylation Inhibitor [EPC]
Route: ORAL
Dosage Form: TABLET, FILM COATED
Product Type: HUMAN PRESCRIPTION DRUG

Description

11 DESCRIPTION Carbidopa, levodopa and entacapone tablets are a combination of carbidopa, levodopa, and entacapone for the treatment of Parkinson’s disease. Carbidopa USP, an inhibitor of aromatic amino acid decarboxylation, is a white to creamy white powder, freely soluble in 3 N hydrochloric acid; slightly soluble in water and in methanol; practically insoluble in alcohol, in acetone, in chloroform and in ether, with a molecular weight of 244.3. It is designated chemically as (-)-L-(α-hydrazino-(α-methyl-β-(3,4-dihydroxybenzene) propanoic acid monohydrate. Its empirical 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 226.3. Levodopa USP, an aromatic amino acid, is a white to off-white, crystalline powder, slightly soluble in water, freely soluble in 3 N hydrochloric acid and insoluble in alcohol, with a molecular weight of 197.2. It is designated chemically as (-)-L-α-amino-β-(3,4-dihydroxybenzene) propanoic acid. Its empirical formula is C 9 H 11 NO 4 , and its structural formula is: Entacapone USP, a COMT inhibitor, is a nitro-catechol-structured compound with a molecular weight of 305.3. The chemical name of entacapone is (E)-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl)-N,N-diethyl-2-propenamide. Its empirical formula is C 14 H 15 N 3 O 5 and its structural formula is: Carbidopa, levodopa and entacapone is supplied as tablets in 6 strengths: Carbidopa, levodopa and entacapone tablets 12.5 mg/50 mg/200 mg: 12.5 mg of carbidopa USP, 50 mg of levodopa USP and 200 mg of entacapone USP. Carbidopa, levodopa and entacapone tablets 18.75 mg/75 mg/200 mg: 18.75 mg of carbidopa USP, 75 mg of levodopa USP and 200 mg of entacapone USP. Carbidopa, levodopa and entacapone tablets 25 mg/100 mg/200 mg: 25 mg of carbidopa USP, 100 mg of levodopa USP and 200 mg of entacapone USP. Carbidopa, levodopa and entacapone tablets 31.25 mg/125 mg/200 mg: 31.25 mg of carbidopa USP,...

What Is Carbidopa, Levodopa And Entacapone Used For?

1 INDICATIONS AND USAGE Carbidopa, levodopa and entacapone tablets are indicated for the treatment of Parkinson’s disease. Carbidopa, levodopa and entacapone tablets can be used:

To substitute (with equivalent strengths of each of the three components) carbidopa/levodopa and entacapone previously administered as individual products.

To replace carbidopa/levodopa therapy (without entacapone) when patients experience the signs and symptoms of end-of-dose “wearing-off” and when they have been taking a total daily dose of levodopa of 600 mg or less and have not been experiencing dyskinesias. Carbidopa, levodopa and entacapone tablets, a combination drug consisting of levodopa (aromatic amino acid), carbidopa (aromatic amino acid decarboxylation inhibitor), and entacapone (catechol-O-methyltransferase (COMT) inhibitor) is indicated for the treatment of Parkinson’s disease. Carbidopa, levodopa and entacapone tablets are to be used:

To substitute (with equivalent strengths of each of the three components) for carbidopa/levodopa and entacapone previously administered as individual products ( 1 )

Dosage and Administration

2 DOSAGE AND ADMINISTRATION Carbidopa, levodopa and entacapone tablets should be used as a substitute for patients already stabilized on equivalent doses of carbidopa/levodopa and entacapone. However, some patients who have been stabilized on a given dose of carbidopa/levodopa may be treated with carbidopa, levodopa and entacapone tablets if a decision has been made to add entacapone (see below). Therapy should be individualized and adjusted according to the desired therapeutic response.

The optimum daily dosage of carbidopa, levodopa and entacapone tablets must be determined by careful titration in each patient ( 2.1 )

Individual tablets should not be split or fractionated. Administer only one tablet at each dosing interval ( 2.6 ) 2.1 Dosing Information The optimum daily dosage of carbidopa, levodopa and entacapone tablets must be determined by careful titration in each patient. Clinical experience with daily doses above 1,600 mg of entacapone is limited. The maximum recommended daily dose of carbidopa, levodopa and entacapone tablets depends on the strength used. The maximum number of tablets to be used in a 24-hour period is less with the highest strength (carbidopa, levodopa and entacapone tablets 50 mg/200 mg/200 mg) than with lower strengths (see Table 1). Studies show that peripheral dopa decarboxylase is saturated by carbidopa at approximately 70 mg per day to 100 mg per day. Patients receiving less than this amount of carbidopa are more likely to experience nausea and vomiting. Table 1: Maxium Recommended Dose of Carbidopa, Levodopa and Entacapone Tablets in a 24-hour Period Carbidopa, Levodopa and Entacapone Tablets Dosage Strength Maximum Number of Tablets in a 24-hour Period 12.5 mg/50 mg/200 mg, 18.75 mg/75 mg/200 mg, 25 mg/100 mg/200 mg, 31.25 mg/125 mg/200 mg, 37.5 mg/150 mg/200 mg 8 50 mg/200 mg/200 mg 6 2.2 Converting Patients from Carbidopa, Levodopa, and Entacapone to Carbidopa, Levodopa and Entacapone Tablets Patients currently treated with entacapone 200 mg with each dose of non-extended release carbidopa/levodopa tablet, can switch to the corresponding strength of carbidopa, levodopa and entacapone tablets containing the same amounts of levodopa and carbidopa. For example, patients receiving one tablet of carbidopa/levodopa 25 mg/100 mg and one tablet of entacapone 200 mg at each administration can switch to a single carbidopa, levodopa and entacapone tablet (containing 25 mg of carbidopa, 100 mg of levodopa and 200 mg of entacapone). 2.3 Converting Patients from Carbidopa and Levodopa Products to Carbidopa, Levodopa and Entacapone Tablets There is no experience in transferring patients currently treated with extended release formulations of carbidopa/levodopa, or carbidopa/levodopa products that are not combined in a 1:4 ratio of carbidopa to levodopa. Patients with a history of moderate or severe dyskinesias or taking more than 600 mg of the levodopa component per day are likely to require a reduction in their daily...

Side Effects (Adverse Reactions)

6 ADVERSE REACTIONS The following adverse reactions are discussed in more detail in the Warnings and Precautions sections of labeling:

Falling Asleep During Activities of Daily Living and Somnolence [see Warnings and Precautions (5.1)]

Hypotension/Orthostatic Hypotension and Syncope [see Warnings and Precautions (5.2)]

Dyskinesia [see Warnings and Precautions (5.3)]

Depression and suicidality [see Warnings and Precautions (5.4)]

Hallucinations/Psychotic-Like Behavior [see Warnings and Precautions (5.5)]

Impulse Control and/or Compulsive Behaviors [see Warnings and Precautions (5.6)]

Withdrawal-Emergent Hyperpyrexia and Confusion [ see Warnings and Precautions (5.7)]

Diarrhea and Colitis [see Warnings and Precautions (5.8)]

Rhabdomyolysis [see Warnings and Precautions (5.9)]

Peptic Ulcer Disease [see Warnings and Precautions (5.13)] The most common adverse reactions (incidence 3% higher than placebo incidence) are dyskinesias, hyperkinesia, diarrhea, nausea, abdominal pain, vomiting, dry mouth, and urine discoloration ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Alembic Pharmaceuticals Limited at 1-866-210-9797 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, the incidence of adverse reactions (number of unique patients experiencing an adverse reaction associated with treatment/total number of patients treated) observed in the clinical trials of a drug cannot be directly compared to the incidence of adverse reactions in the clinical trials of another drug and may not reflect the incidence of adverse reactions observed in clinical practice. Entacapone The most commonly observed adverse reactions (incidence at least 3% greater than placebo incidence) in the double-blind, carbidopa-levodopa-placebo-controlled trials of entacapone (N=1,003 patients) associated with the use of carbidopa-levodopa-entacapone alone and not seen at an equivalent frequency among the placebo-treated patients were: dyskinesia, diarrhea, nausea, hyperkinesia, abdominal pain, vomiting, dry mouth, and urine discoloration. The treatment difference incidence for premature study discontinuation for entacapone with levodopa and dopa decarboxylase inhibitor in the double-blind, placebo-controlled trials was 5%. The treatment difference incidence for the most frequent causes of study discontinuation was 2% for diarrhea, and 1% for other specific adverse reactions including psychiatric reasons, dyskinesia/ hyperkinesia, nausea, or abdominal pain. Adverse Reaction Incidence in Controlled Clinical Studies of Entacapone Table 2 lists treatment emergent adverse reactions that occurred in at least 1% of patients treated with carbidopa/levodopa and 200 mg of entacapone who participated in the double-blind, placebo-controlled studies, and that were numerically more common in this group than in the carbidopa/levodopa plus placebo group. In these studies, either entacapone or placebo was added to carbidopa/levodopa (or benserazide/levodopa). Table 2: Summary of Patients With Adverse Reactions After Start of Trial Drug Administration At Least 1% in Entacapone Group and Greater Than Placebo SYSTEM ORGAN CLASS Carbidopa/levodopa plus Entacapone Carbidopa/levodopa plus Placebo Adverse Reaction (n=603) % of patients (n=400) % of patients SKIN AND APPENDAGES DISORDERS Sweating Increased 2 1 MUSCULOSKELETAL SYSTEM DISORDERS Back Pain 5 3 CENTRAL AND PERIPHERAL NERVOUS SYSTEM DISORDERS Dyskinesia 25 15 Hyperkinesia 10 5 Hypokinesia 9 8 Dizziness 8 6 SPECIAL SENSES, OTHER DISORDERS Taste Perversion 1 0 PSYCHIATRIC DISORDERS Anxiety 2 1 Somnolence 2 0 Agitation 1 0 GASTROINTESTINAL SYSTEM DISORDERS Nausea 14 8 Diarrhea 10 4 Abdominal Pain 8 4 Constipation 6 4 Vomiting 4 1 Mouth Dry 3 0 Dyspepsia 2 1 Flatulence 2 0 Gastritis 1 0 Gastrointestinal Disorders NOS 1 0 RESPIRATORY SYSTEM DISORDERS Dyspnea 3 1 PLATELET, BLEEDING AND CLOTTING DISORDERS Purpura 2...

Drug Interactions

7 DRUG INTERACTIONS

Drugs metabolized by COMT: use with caution ( 5.11 , 7.2 )

Anti-hypertensive agents: dose adjustment may be required ( 7.3 )

Tricyclic antidepressants: risk of hypertension and dyskinesia reported during concomitant use with carbidopa/levodopa ( 7.4 )

Dopamine D2 receptor antagonists, isoniazid, phenytoin, papaverine and iron salts: may reduce efficacy of carbidopa, levodopa and entacapone tablets ( 7.5 , 7.6 , 7.7 , 7.8 , 7.9 )

Drugs that interfere with biliary excretion, glucuronidation and intestinal beta-glucuronidase: dose adjustment of carbidopa, levodopa and entacapone tablets may be required ( 7.10 )

Drugs metabolized by CYP2C9 (e.g., coumadin): dose adjustment of carbidopa, levodopa and entacapone tablets may be required; monitor INR when initiating carbidopa, levodopa and entacapone tablets in patients on coumadin ( 7.11 ) 7.1 MAO Inhibitors Patients receiving nonselective MAO inhibitors and carbidopa, levodopa and entacapone may be at risk of increased adrenergic tone. Therefore, the use of carbidopa, levodopa and entacapone tablets is contraindicated in patients receiving nonselective MAO inhibitors [see Contraindications (4)]. 7.2 Drugs Metabolized by Catechol-O-Methyltransferase (COMT) Drugs known to be metabolized by COMT, such as isoproterenol, epinephrine, norepinephrine, dopamine, dobutamine, alpha-methyldopa, apomorphine, isoetherine, and bitolterol should be administered with caution in patients receiving entacapone regardless of the route of administration (including inhalation), as their interaction may result in increased heart rates, possibly arrhythmias, and excessive changes in blood pressure [see Warnings and Precautions ((5.10)]. 7.3 Antihypertensive Agents Symptomatic postural hypotension has occurred when carbidopa/levodopa was added to the treatment of patients receiving antihypertensive drugs. When starting therapy with carbidopa, levodopa and entacapone tablets, dosage adjustment of antihypertensive drug may be required. 7.4 Tricyclic Antidepressants There have been reports of adverse reactions, including hypertension and dyskinesia, resulting from the concomitant use of tricyclic antidepressants and carbidopa/levodopa. 7.5 Dopamine D2 Receptor Antagonists Dopamine D2 receptor antagonists (e.g., metoclopramide, phenothiazines, butyrophenones, risperidone) may reduce the therapeutic effects of levodopa. 7.6 Isoniazid Isoniazid may reduce the therapeutic effects of levodopa, a dose increase may be necessary. 7.7 Phenytoin The beneficial effects of levodopa in Parkinson’s disease have been reported to be reversed by phenytoin. Patients taking phenytoin with carbidopa/levodopa should be carefully observed for loss of therapeutic response. Carbidopa, levodopa and entacapone tablets dosage should be increased as clinically needed in patients receiving phenytoin. 7.8 Papaverine The beneficial effects of levodopa in Parkinson’s disease have been reported to be reversed by papaverine....

Contraindications

4 CONTRAINDICATIONS Carbidopa, levodopa and entacapone tablets are contraindicated in patients:

Taking nonselective monoamine oxidase (MAO) inhibitors (e.g., phenelzine and tranylcypromine). These nonselective MAO inhibitors must be discontinued at least two weeks prior to initiating therapy with carbidopa, levodopa and entacapone tablets.

With narrow-angle glaucoma.

Concomitant use of nonselective monoamine oxidase (MAO) inhibitors ( 4 )

Narrow-angle glaucoma ( 4 )

Pregnancy and Breastfeeding

8.1 Pregnancy Risk Summary There are no adequate data on the developmental risk associated with the use of carbidopa, levodopa and entacapone tablets in pregnant women. In animals, administration of carbidopa-levodopa or entacapone during pregnancy was associated with developmental toxicity, including increased incidences of fetal malformations (see Data) . The estimated background risk of major birth defects and miscarriage in the indicated population is unknown. In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies are 2 to 4% and 15 to 20%, respectively. Data Animal data In nonclinical studies in which carbidopa-levodopa was administered to pregnant animals, increased incidences of visceral and skeletal malformations were observed in rabbits at all doses and ratios of carbidopa-levodopa tested, which ranged from 10 times (carbidopa)-5 times (levodopa) to 20 times (carbidopa)-10 times (levodopa) the maximum recommended human dose (MRHD) of 1,600 mg/day. In rats, there was a decrease in the number of live pups delivered by dams receiving approximately two times (carbidopa)-five times (levodopa) the MRHD throughout organogenesis. No effects on malformation frequencies were observed in mice receiving up to 20 times the MRHD of carbidopa-levodopa. In embryo-fetal development studies of entacapone, pregnant animals received doses of up to 1,000 mg/kg/day (rats) or 300 mg/kg/day (rabbits) throughout organogenesis. Increased incidences of fetal variations were evident in litters from rats treated with the highest dose, in the absence of overt signs of maternal toxicity. The maternal plasma entacapone exposure (AUC) associated with this dose was approximately 34 times that in humans at the MRHD. Increased frequencies of abortions and late/total resorptions and decreased fetal weights were observed in the litters of rabbits treated with maternally toxic doses of 100 mg/kg/day (plasma AUCs...

Overdosage

10 OVERDOSAGE 10.1 Signs and Symptoms of Overdosage There are very few cases of overdose with levodopa reported in the published literature. Based on the available information, the acute symptoms of levodopa and dopa decarboxylase inhibitor overdose can be expected to arise from dopaminergic overstimulation. Doses of a few grams may result in CNS disturbances, with an increasing likelihood of cardiovascular disturbance (e.g., hypotension, tachycardia) and more severe psychiatric problems at higher doses. An isolated report of rhabdomyolysis and another of transient renal insufficiency suggest that levodopa overdose may give rise to systemic complications, secondary to dopaminergic overstimulation. COMT inhibition by entacapone treatment is dose-dependent. A massive overdose of entacapone may theoretically produce a 100% inhibition of the COMT enzyme in people, thereby preventing the O-methylation of endogenous and exogenous catechols. In clinical trials, the highest single dose of entacapone administered to humans was 800 mg, resulting in a plasma concentration of 14.1 mcg per mL. The highest daily dose given to humans was 2,400 mg, administered in one study as 400 mg six times daily with carbidopa/levodopa for 14 days in 15 Parkinson’s disease patients, and in another study as 800 mg three times daily for 7 days in 8 healthy volunteers. At this daily dose, the peak plasma concentrations of entacapone averaged 2 mcg per mL (at 45 min, compared to 1 mcg per mL and 1.2 mcg per mL with 200 mg entacapone at 45 min.). Abdominal pain and loose stools were the most commonly observed adverse events during this study. Daily doses as high as 2,000 mg entacapone have been administered as 200 mg 10 times daily with carbidopa/levodopa or benserazide/levodopa for at least 1 year in 10 patients, for at least 2 years in 8 patients and for at least 3 years in 7 patients. Overall, however, clinical experience with daily doses above 1,600 mg is limited. 10.2 Management of Overdosage...

How Supplied

16 HOW SUPPLIED/STORAGE AND HANDLING Carbidopa, levodopa and entacapone tablets are supplied as film coated tablets for oral administration in the following six strengths: Carbidopa, levodopa and entacapone tablets 12.5 mg/50 mg/200 mg film coated tablets containing 12.5 mg of carbidopa USP, 50 mg of levodopa USP and 200 mg of entacapone USP. The round, biconvex shaped tablets are brownish- or greyish- red, unscored, and debossed with “L 528” on one side and plain on other side. Bottle of 100 tablets with child-resistant closure, NDC 62332-795-31 Bottle of 1000 tablets, NDC 62332-795-91 Carbidopa, levodopa and entacapone tablets 18.75 mg/75 mg/200 mg film coated tablets containing 18.75 mg of carbidopa USP, 75 mg of levodopa USP and 200 mg of entacapone USP. The oval shaped tablets are light brownish red, unscored, and debossed with “C J” on one side and plain on other side. Bottle of 100 tablets with child-resistant closure, NDC 62332-796-31 Bottle of 1000 tablets, NDC 62332-796-91 Carbidopa, levodopa and entacapone tablets 25 mg/100 mg/200 mg film coated tablets containing 25 mg of carbidopa USP, 100 mg of levodopa USP and 200 mg of entacapone USP. The oval shaped tablets are brownish or greyish red, unscored, and debossed with “J J” on one side and plain on other side. Bottle of 100 tablets with child-resistant closure, NDC 62332-797-31 Bottle of 1000 tablets, NDC 62332-797-91 Carbidopa, levodopa and entacapone tablets 31.25 mg/125 mg/200 mg film coated tablets containing 31.25 mg of carbidopa USP, 125 mg of levodopa USP and 200 mg of entacapone USP. The oval shaped tablets are light brownish red, unscored, and debossed with “L C” on one side and plain on other side. Bottle of 100 tablets with child-resistant closure, NDC 62332-798-31 Bottle of 1000 tablets, NDC 62332-798-91 Carbidopa, levodopa and entacapone tablets, 37.5 mg/150 mg/200 mg film coated tablets containing 37.5 mg of carbidopa USP, 150 mg of levodopa USP and 200 mg of entacapone USP. The elongated...

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.