Aromatic Amino Acid

Carbidopa and Levodopa

Approved 18 Sept 2008OralTablet, orally disintegrating

The FDA lists this product in 60 strengths and forms.

Indications

Carbidopa and levodopa orally disintegrating 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 orally disintegrating tablets.

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.

Contraindications

Nonselective monoamine oxidase (MAO) inhibitors are contraindicated for use with carbidopa and levodopa orally disintegrating tablets. These inhibitors must be discontinued at least two weeks prior to initiating therapy with carbidopa and levodopa orally disintegrating tablets. Carbidopa and levodopa orally disintegrating tablets 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 orally disintegrating tablets are contraindicated in patients with known hypersensitivity to any component of this drug, and in patients with narrow-angle glaucoma.

Warnings and precautions

When carbidopa and levodopa orally disintegrating tablets are to be given to patients who are being treated with levodopa, levodopa must be discontinued at least twelve hours before therapy with carbidopa and levodopa orally disintegrating tablets are 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 carbidopa and levodopa orally disintegrating tablets 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.

Indications

Contraindications

Carbidopa and levodopa orally disintegrating tablets are contraindicated in patients with known hypersensitivity to any component of this drug, and in patients with narrow-angle glaucoma.

Warnings and precautions

Interactions

Drug Interactions Caution should be exercised when the following drugs are administered concomitantly with carbidopa and levodopa orally disintegrating tablets. Symptomatic postural hypotension occurred when carbidopa and levodopa orally disintegrating tablets was added to the treatment of a patient receiving antihypertensive drugs. Therefore, when therapy with carbidopa and levodopa orally disintegrating tablets is started, dosage adjustment of the antihypertensive drug may be required.

For patients receiving MAO inhibitors (Type A or B), see CONTRAINDICATIONS. Concomitant therapy with selegiline and carbidopa and levodopa may be associated with severe orthostatic hypotension not attributable to carbidopa and levodopa alone (see CONTRAINDICATIONS). There have been rare reports of adverse reactions, including hypertension and dyskinesia, resulting from the concomitant use of tricyclic antidepressants and carbidopa and levodopa orally disintegrating tablets.

Dopamine D 2 receptor antagonists (e.g., phenothiazines, butyrophenones, risperidone) and isoniazid may reduce the therapeutic effects of levodopa. In addition, the beneficial effects of levodopa in Parkinson’s disease have been reported to be reversed by phenytoin and papaverine. Patients taking these drugs with carbidopa and levodopa orally disintegrating tablets should be carefully observed for loss of therapeutic response.

Use of carbidopa and levodopa orally disintegrating tablets with dopamine-depleting agents (e.g., reserpine and tetrabenazine) or other drugs known to deplete monoamine stores is not recommended. Carbidopa and levodopa orally disintegrating tablets and iron salts or multivitamins containing iron salts should be coadministered with caution. Iron salts can form chelates with levodopa and carbidopa and consequently reduce the bioavailability of carbidopa and levodopa.

Although metoclopramide may increase the bioavailability of levodopa by increasing gastric emptying, metoclopramide may also adversely affect disease control by its dopamine receptor antagonistic properties.

Adverse reactions

The most common adverse reactions reported with carbidopa and levodopa orally disintegrating tablets 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 carbidopa and levodopa orally disintegrating tablets 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 REACTIONS, contact Rising Pharma Holdings, Inc. at 1-844-874-7464 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Carbidopa and Levodopa

Indications

Contraindications

Warnings and precautions

Two medicines in one question?

Carbidopa and Levodopa

Indications

Contraindications

Warnings and precautions

Two medicines in one question?

Interactions

Pregnancy and breastfeeding

Adverse reactions

Composition

Strengths and forms

Official product information

At a glance