LODOSYN- carbidopa tablet
Aton Pharma, Inc
Rx only
When LODOSYN (carbidopa) is to be given to carbidopa-naive patients who are being treated with levodopa, the two drugs should be given at the same time, starting with no more than 20 to 25% of the previous daily dosage of levodopa when given without LODOSYN (carbidopa). At least twelve hours should elapse between the last dose of levodopa and initiation of therapy with LODOSYN (carbidopa) and levodopa. See the WARNINGS and DOSAGE AND ADMINISTRATION sections before initiating therapy.
DESCRIPTION
Carbidopa, an inhibitor of aromatic amino acid decarboxylation, is a white, crystalline compound, slightly soluble in water, with a molecular weight of 244.3. It is designated chemically as (�)-L-?-hydrazino-?-methyl-?-(3,4-dihydroxybenzene) propanoic acid monohydrate. Its empirical formula is C10 H14 N2 O4 �H2 O, and its structural formula is:
Chemical Structure
(click image for full-size original)
LODOSYN (carbidopa) tablets contain 25 mg of carbidopa. Inactive ingredients are cellulose, FD&C Yellow No. 6, magnesium stearate and starch.
Tablet content is expressed in terms of anhydrous carbidopa which has a molecular weight of 226.3.
CLINICAL PHARMACOLOGY
Parkinson�s disease is a progressive, neurodegenerative disorder of the extrapyramidal nervous system affecting the mobility and control of the skeletal muscular system. Its characteristic features include resting tremor, rigidity, and bradykinetic movements. Symptomatic treatments, such as levodopa therapies, may permit the patient better mobility.
Mechanism of Action
Current evidence indicates that symptoms of Parkinson�s disease are related to depletion of dopamine in the corpus striatum. Administration of dopamine is ineffective in the treatment of Parkinson�s disease apparently because it does not cross the blood-brain barrier. However, levodopa, the metabolic precursor of dopamine, does cross the blood-brain barrier, and presumably is converted to dopamine in the brain. This is thought to be the mechanism whereby levodopa relieves symptoms of Parkinson�s disease.
