Dosing and uses of Lodosyn (carbidopa)
Adult dosage forms and strengths
(tablet)
- 25 mg
Parkinson's Disease
For use with carbidopa-levodopa or with levodopa for Parkinson's disease in patients for whom the dosage of carbidopa-levodopa combo provides less than adequate daily dosage of carbidopa, or in patients whose dosage requirement of carbidopa & levodopa necessitates separate titration of each entity
Dosage dependent upon concurrent dose of carbidopa-levodopa or levodopa & patient's specific needs
Patients taking Sinemet 10/100: Administer 25 mg carbidopa daily with first daily dose of Sinemet 10/100 if necessary; may administer 12.5-25 mg carbidopa with each subsequent dose of Sinemet 10/100; not to exceed 200 mg carbidopa/day including carbidopa from Sinemet
Patients taking Sinemet 25/250 or 25/100: Administer 25 mg carbidopa daily with either Sinemet strength throughout the day; not to exceed 200 mg/day of carbidopa including the Sinemet combination
Titration of carbidpa and levodopa (individually)
- Administer 25 mg carbidopa PO q6-8hr concurrently with levodopa; administer 20-25% less than the previous levodopa in carbidopa naive patients; first dose of carbidopa should be taken ≤12hr after the test dose of levodopa in carbidopa naive patients; increase or decrease dose by 1/2 or 1 tab/day
Pediatric dosage forms and strengths
Safety & efficacy in children not established
Pharmacology of Lodosyn (carbidopa)
Mechanism of action
Inhibits the aromatic amino-acid decarboxylase enzyme & conversion of levodopa to dopamine peripherally, which in turn reduces peripheral side-effects including nausea, vomiting, and cardiac arrhythmias; does not counter central effects of levodopa

