Carbidopa and Levodopa 10 mg; 100 mg Tablet, 100-count — NDC 59651-456-01 (Billing 59651-0456-01)

WARNINGS When carbidopa and levodopa is 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 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 carbidopa and levodopa 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. 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 carbidopa and levodopa 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 carbidopa and levodopa may increase the possibility of upper gastrointestinal hemorrhage in patients with a history of peptic ulcer. Vitamin B 6 Deficiency and Seizures Treatment with carbidopa and levodopa may contribute to reduced vitamin B 6 levels.

Higher doses of carbidopa/levodopa may increase the risk of vitamin B 6 deficiency. Seizures associated with vitamin B 6 deficiency have been reported in the postmarketing setting in patients taking carbidopa and levodopa. In these reported cases, seizures were refractory to traditional anti-seizure medications and only resolved after vitamin B 6 administration.

Other symptoms of vitamin B 6 deficiency may occur, including depression, confusion, cheilosis, glossitis, dermatitis, anemia, and/or neuropathy. Evaluate vitamin B 6 levels prior to initiation of carbidopa and levodopa and periodically while on treatment or if symptoms associated with vitamin B 6 deficiency are identified. Supplement with vitamin B 6 as necessary.

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 pre-existing 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 ca… [Excerpted — this section continues on DailyMed.]

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, seizures (including convulsions).

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 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; decreased vitamin B 6 levels.

Drug Interactions Caution should be exercised when the following drugs are administered concomitantly with carbidopa and levodopa. Symptomatic postural hypotension occurred when carbidopa and levodopa was added to the treatment of a patient receiving antihypertensive drugs. Therefore, when therapy with carbidopa and levodopa 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.

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 should be carefully observed for loss of therapeutic response.

Use of carbidopa and levodopa with dopamine-depleting agents (e.g., reserpine and tetrabenazine) or other drugs known to deplete monoamine stores is not recommended. Carbidopa and levodopa 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.

PRECAUTIONS General As with levodopa, periodic evaluations of hepatic, hematopoietic, cardiovascular, and renal function are recommended during extended therapy. Patients with chronic wide-angle glaucoma may be treated cautiously with carbidopa and levodopa provided the intraocular pressure is well-controlled and the patient is monitored carefully for changes in intraocular pressure during therapy. Dyskinesia Levodopa alone, as well as carbidopa and levodopa, is associated with dyskinesias.

The occurrence of dyskinesias may require dosage reduction. Hallucinations / Psychotic-Like Behavior Hallucinations and psychotic-like behavior have been reported with dopaminergic medications. In general, hallucinations present shortly after the initiation of therapy and may be responsive to dose reduction in levodopa.

Hallucinations may be accompanied by confusion and to a lesser extent sleep disorder (insomnia) and excessive dreaming. Carbidopa and levodopa may have similar effects on thinking and behavior. This abnormal thinking and behavior may present with one or more symptoms, including paranoid ideation, delusions, hallucinations, confusion, psychotic-like behavior, disorientation, aggressive behavior, agitation, and delirium.

Ordinarily, patients with a major psychotic disorder should not be treated with carbidopa and levodopa, because of the risk of exacerbating psychosis. In addition, certain medications used to treat psychosis may exacerbate the symptoms of Parkinson’s disease and may decrease the effectiveness of carbidopa and levodopa. Impulse Control / Compulsive Behaviors Reports of patients taking dopaminergic medications (medications that increase central dopaminergic tone), suggest that patients may experience an intense urge to gamble, increased sexual urges, intense urges to spend money, binge eating, and/or other intense urges, and the inability to control these urges.

In some cases, although not all, these urges were reported to have stopped when the dose was reduced or the medication was discontinued. Because patients may not recognize these behaviors as abnormal, it is important for prescribers to specifically ask patients or the caregivers about the development of new or increased gambling urges, sexual urges, uncontrolled spending or other urges while being treated with carbidopa and levodopa. Physicians should consider dose reduction or stopping the medication if a patient develops such urges while taking carbidopa and levodopa [see Information for Patients ].

Melanoma Epidemiological studies have shown that patients with Parkinson’s disease have a higher risk (2- to approximately 6-fold higher) of developing melanoma than the general population. Whether the increased risk observed was due to Parkinson’s disease or other factors, such as drugs used to treat Parkinson’s disease, is unclear. For the reasons stated above, patients and providers are advised to monitor for melanomas frequently and on a regular basis when using carbidopa and levodopa for any indication.

Ideally, periodic skin examinations should be performed by appropriately qualified individuals (e.g., dermatologists). Information for Patients The patient should be informed that carbidopa and levodopa is an immediate-release formulation of carbidopa and levodopa that is designed to begin release of ingredients within 30 minutes. It is important that carbidopa and levodopa be taken at regular intervals according to the schedule outlined by the physician.

The patient should be cautioned not to change the prescribed dosage regimen and not to add any additional antiparkinson medications, including other carbidopa and levodopa preparations, without first consulting the physician. Patients should be advised that sometimes a ‘wearing-off’ effect may occur at the end of the dosing interval. The physician should be notified if such response poses a problem to lifestyle.

Patients should be advised that occasionally, dark color (red, brown, or black) may appear… [Excerpted — this section continues on DailyMed.]