Levodopa + Carbidopa + Entacapone

This medicine is indicated for the treatment of adult patients with Parkinson's disease and end-of-dose motor fluctuations not stabilized on levodopa/dopa decarboxylase (DDC) inhibitor treatment.

Levodopa is the metabolic precursor of dopamine. It crosses the blood-brain barrier and is converted to dopamine in the brain. Carbidopa increases the amount of levodopa that is transported into the CNS by inhibiting the decarboxylation of peripheral levodopa. Entacapone is a selective inhibitor of COMT which alters the pharmacokinetics of levodopa, resulting to increased and more sustained levodopa serum levels.

Adults: The optimum daily dose must be determined by careful titration of levodopa in each patient. Patients should be instructed to take only 1 (one) tablet per dose administration. The maximum recommended daily dose of entacapone is 2,000 mg. Usually this combination is to be used in patients who are currently treated with corresponding doses of standard release Levodopa or Dopa Decarboxylase (DDC) inhibitor and entacapone.

Administration

May be taken with or without food. Keep a consistent diet. A change in diet to foods high in protein may delay levodopa absorption & reduce amount taken up in circulation. Excessive acidity also delays stomach emptying & thus delays levodopa absorption. Iron salts may also reduce amount of levodopa available to the body. Swallow whole.

Symptomatic postural hypotension may occur when levodopa is added to the treatment of patients already receiving antihypertensive. Dose adjustment of the antihypertensive agent may be required. Dopamine receptor antagonists (e.g. some antipsychotics and antiemetics), phenytoin and papaverine may reduce the therapeutic effect of levodopa. Patients taking these medicinal products with levodopa/ carbidopa/ entacapone combination should be carefully observed for loss of therapeutic response. Since levodopa competes with certain amino acids, the absorption of Levodopa, Carbidopa & Entacapone may be impaired in some patients on high protein diet.

Narrow-angle glaucoma, phaeochromocytoma, history of neuroleptic malignant syndrome (NMS) and/ or non-traumatic rhabdomyolysis. Severe hepatic impairment. Concurrent use of or within 14 days of discontinuing non-selective MAOIs.

Common side effects include dyskinesia, nausea, hyperkinesia, change in urine color, diarrhea and stomach pain. Other side effects may include diarrhea, sometimes severe; colitis; hallucinations; other mental disturbances; orthostatic hypotension; rhabdomyolysis; and symptoms resembling neuroleptic malignant syndrome (a condition characterized by high fever, muscle stiffness, and confusion); fibrosis; skin cancer, etc.

Pregnancy category C. The combination of levodopa/ carbidopa/ entacapone should not be used during pregnancy unless the potential benefit justifies the potential risk to the fetus. The safety of this combination in the infant is not known. Women should not breast-feed during treatment with this combination.

Levodopa, carbidopa and entacapone together may cause dizziness and symptomatic orthostatism. Therefore, caution should be exercised when driving or using machines. As with levodopa, periodic evaluations of hepatic, hematopoietic, cardiovascular and renal function are recommended during extended therapy.

The acute symptoms and signs of overdose include agitation, confusional state, coma, bradycardia, ventricular tachycardia, Cheyne Stokes respiration, discolorations of skin, tongue and conjunctiva, and chromaturia. Management of acute overdose with levodopa/ carbidopa/ entacapone combination is similar to acute overdose with levodopa. Pyridoxine, however, is not effective in reversing the actions of levodopa/ carbidopa/ entacapone combination. Hospitalization is advised and general supportive measures should be employed with immediate gastric lavage and repeated doses of charcoal over time.

Antiparkinson drugs

Children: Safety and effectiveness in pediatric patients have not been established.

Elderly: No dose adjustment is required for elderly patients.

Hepatic impaired patients: Should be administered cautiously to patients with mild to moderate hepatic impairment. Dose reduction may be needed.

Renally impaired patients: Should be administered cautiously to patients in severe renal impairment including those receiving dialysis therapy

Store in a cool and dry place. Protect from light.