SINEMET

SINEMET is an FDA-registered drug product whose active ingredient is CARBIDOPA AND LEVODOPA. It is labelled by Organon LLC taken by oral and marketed as a human prescription drug product. Identifiers on file: NDC 78206-166, application NDA017555, label effective 20260801. It is one of 32 FDA drug label records sharing the active ingredient CARBIDOPA AND LEVODOPA. This page reproduces the FDA-approved label text so you can check what a product is, who makes it and how it is supplied before discussing it with a pharmacist or prescriber.

Across FDA labelling, products containing CARBIDOPA AND LEVODOPA are most often described in connection with: parkinson disease, usage sinemet, post-encephalitic parkinsonism, follow carbon, monoxide intoxication, carbidopa allows, patients treated, much lower. Wording differs between labels, and the full indications section on this page takes precedence when it is present.

INDICATIONS AND USAGE SINEMET is 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 SINEMET. 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 SINEMET 25-250 tablets are no longer marketed. For dosing with 25-250 strength, use another carbidopa and levodopa product. The optimum daily dosage of SINEMET must be determined by careful titration in each patient. SINEMET tablets are available in a 1:4 ratio of carbidopa to levodopa (SINEMET 25-100) as well as 1:10 ratio (carbidopa and levodopa 25-250 and SINEMET 10-100). 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. Management of Vitamin B 6 Levels Evaluate vitamin B 6 levels prior to initiating carbidopa/levodopa therapies, including SINEMET, periodically during treatment, and as clinically indicated (see WARNINGS, Vitamin B6 Deficiency and Seizures ). If vitamin B 6 levels are low, supplement to sufficient levels per standard of care. Patients may initiate and continue treatment with SINEMET while supplementing vitamin B 6 . Usual Initial Dosage Dosage is best initiated with one tablet of SINEMET 25-100 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 SINEMET 25-100 a day is reached. If SINEMET 10-100 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 q.i.d.) is reached. How to Transfer Patients from Levodopa Levodopa must be discontinued at least twelve hours before starting SINEMET. A daily dosage of SINEMET should be chosen that will provide approximately 25% of the previous levodopa dosage. Patients who are taking less than 1500 mg of levodopa a day should be started on one tablet of SINEMET 25-100 three or four times a day. The suggested starting dosage for most patients taking more than 1500 mg of levodopa is one tablet of carbidopa and levodopa 25-250 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 tablet of SINEMET 25-100 may be substituted for each tablet of SINEMET 10-100. When more levodopa is required, carbidopa and levodopa 25-250 should be substituted for SINEMET 25-100 or SINEMET 10-100. If necessary, the dosage of carbidopa and levodopa 25-250 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 SINEMET than with levodopa alone, patients should be monitored closely during the dose adjustment period. Specifically, involuntary movements will occur more rapidly with SINEMET 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 SINEMET 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 SINEMET. Patients should be observed carefully if abrupt reduction or discontinuation of SINEMET is required, especially if the patient is receiving neuroleptics. (See WARNINGS .) If general anesthesia is required, SINEMET 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 Nonselective monoamine oxidase (MAO) inhibitors are contraindicated for use with SINEMET. These inhibitors must be discontinued at least two weeks prior to initiating therapy with SINEMET. SINEMET 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 ). SINEMET is contraindicated in patients with known hypersensitivity to any component of this drug, and in patients with narrow-angle glaucoma.

WARNINGS When SINEMET is to be given to patients who are being treated with levodopa, levodopa must be discontinued at least twelve hours before therapy with SINEMET 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 SINEMET 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 SINEMET than with levodopa alone. All patients should be observed carefully for the development of depression with concomitant suicidal tendencies. SINEMET 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 SINEMET 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 SINEMET may increase the possibility of upper gastrointestinal hemorrhage in patients with a history of peptic ulcer. Vitamin B 6 Deficiency and Seizures Treatment with SINEMET 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 SINEMET. 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 SINEMET 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 SINEMET 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 SINEMET. Patients who have already experienced somnolence or an episode of sudden sleep onset should not participate in these activities during treatment with SINEMET. Before initiating treatment with SINEMET, advise patients about the potential to develop drowsiness and ask specifically about factors that may increase the risk for somnolence with SINEMET such as the use of concomitant sedating medications and the presence of sleep disorders. Consider discontinuing SINEMET 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 SINEMET continues, patients should be advised not to drive and to avoid other potentially dangerous activities that might result in harm if the patients become somnolent. There is insufficient information to establish that dose reduction will eliminate episodes of falling asleep while engaged in activities of daily living. Hyperpyrexia and Confusion Sporadic cases of a symptom complex resembling neuroleptic malignant syndrome (NMS) have been reported in association with dose reductions or withdrawal of certain antiparkinsonian agents such as levodopa, carbidopa and levodopa, or carbidopa and levodopa extended release. Therefore, patients should be observed carefully when the dosage of levodopa is reduced abruptly or discontinued, especially if the patient is receiving neuroleptics. NMS is an uncommon but life-threatening syndrome characterized by fever or hyperthermia. Neurological findings, including muscle rigidity, involuntary movements, altered consciousness, mental status changes; other disturbances, such as autonomic dysfunction, tachycardia, tachypnea, sweating, hyper- or hypotension; laboratory findings, such as creatine phosphokinase elevation, leukocytosis, myoglobinuria, and increased serum myoglobin have been reported. The early diagnosis of this condition is important for the appropriate management of these patients. Considering NMS as a possible diagnosis and ruling out other acute illnesses (e.g., pneumonia, systemic infection, etc.) is essential. This may be especially complex if the clinical presentation includes both serious medical illness and untreated or inadequately treated extrapyramidal signs and symptoms (EPS). Other important considerations in the differential diagnosis include central anticholinergic toxicity, heat stroke, drug fever, and primary central nervous system (CNS) pathology. The management of NMS should include: 1) intensive symptomatic treatment and medical monitoring and 2) treatment of any concomitant serious medical problems for which specific treatments are available. Dopamine agonists, such as bromocriptine, and muscle relaxants, such as dantrolene, are often used in the treatment of NMS; however, their effectiveness has not been demonstrated in controlled studies.

ADVERSE REACTIONS The most common adverse reactions reported with SINEMET have included dyskinesias, such as choreiform, dystonic, and other involuntary movements, and nausea. The following other adverse reactions have been reported with SINEMET: 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 SINEMET 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.

FDA lists 32 drug label records with CARBIDOPA AND LEVODOPA as the active ingredient. The most common dosage forms and the manufacturers with the most records are summarised below; strengths, pack sizes and inactive ingredients can still differ between apparently similar products.

3 FDA recall record(s) match this product name or manufacturer. A match means the firm or product name appears in the enforcement report; confirm lot numbers and dates against the official FDA notice before acting.

What is SINEMET used for?
INDICATIONS AND USAGE SINEMET is 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 SINEMET. This is most …

Who makes SINEMET?
Organon LLC is the labeler of record for SINEMET. 32 FDA label records share the active ingredient CARBIDOPA AND LEVODOPA, so generic and branded versions may come from different companies; the manufacturer named on your pack is the one that matters for any enquiry.

What form does SINEMET come in?
administered by oral. Strengths and pack sizes vary by label, so compare the NDC on your pack with the identifier listed on this page.

Is SINEMET prescription or over-the-counter?
The FDA label for this product is recorded as human prescription drug. Marketing status can differ between strengths and countries, so check the dispensing rules where you live.

Are there other products containing CARBIDOPA AND LEVODOPA?
Yes. 32 FDA drug label records list CARBIDOPA AND LEVODOPA as the active ingredient. Products with the same active ingredient can usually be substituted only when a prescriber or pharmacist confirms it is appropriate.

Has SINEMET been recalled?
3 FDA recall record(s) match this product name or manufacturer. Review the recall and safety notices section on this page and confirm lot numbers against the official FDA enforcement report.

Where does this information come from?
All content is reproduced from FDA Structured Product Labelling data via openFDA. It is provided for identification and reference only and is not medical advice.