Presentation and Status in Health Basket
To be taken orally.
The optimum daily dosage of Dopicar’ must be determined by careful titration in each patient.
Dopicar Tablets are available in a ratio of 1:10 of carbidopa to levodopa to provide facility for fine dosage titration for each patient.
Most patients can be maintained on 3-6 tablets of Dopicar a day, given in divided doses.
The maximum dosage should not exceed 8 tablets of Dopicar a day, since experience with total daily dosages of carbidopa greater than 200 mg is limited. If further titration of dosage is desired, levodopa should be added to the treatment regimen.
General Considerations: Studies show that the peripheral dopa-decarboxylase is fully inhibited (saturated) by carbidopa at doses between 70 and 100 mg a day. Patients receiving less than this amount of carbidopa are more likely to experience nausea and vomiting. Patients who require only low doses of levodopa (e.g. less than 700 mg when given as Dopicar), will receive doses of carbidopa which theoretically do not saturate peripheral dopa decarboxylase.
Standard antiparkinsonian drugs, other than levodopa alone, may be continued while Dopicar is being administered, although their dosage may have to be adjusted.
Because both therapeutic and adverse effects are seen more rapidly with Dopicar than with levodopa, patients should be carefully monitored during the dosage adjustment period.
Involuntary movements, particularly blepharospasm, are a useful early sign of excess dosage in some patients.
Patients not currently receiving levodopa: Dosage may be initiated with ½ a tablet of Dopicar 3 times a day, and increased by ½ a tablet every day, or every other day, until a dosage of 3 tablets a day is reached.
If further titration is necessary, dosage with Dopicar may be increased by ½ or 1 tablet every day, or every other day, to a maximum of 8 tablets a day. Alternatively, dosage may be titrated to 6 tablets of Dopicar a day, and further adjusted with increments of levodopa.
Because both therapeutic and adverse responses occurmore rapidly with Dopicar than when levodopa is administered, patients should be monitored closely during the dosage adjustment period. Specifically, involuntary movements will occur more rapidly with Dopicar 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.
Patients receiving levodopa: Levodopa must be discontinued at least 12 hours before Dopicar therapy is initiated. The easiest way to move patients from therapy with levodopa to Dopicar is to initiate Dopicar with the morning dose, after a night when the patient has not received any levodopa. The daily dosage of Dopicar chosen should provide approximately 25% of the previous levodopa daily dosage. The suggested starting dosage for most patients is 1 tablet of Dopicar, 3 or 4 times a day. Patients who require less than 1500 mg of levodopa a day should be started on ½ a tablet of Dopicar, 3 or 4 times a day. Adjustment in dosage may be made as necessary, by adding or omitting ½-1 tablet a day.
Experience with a total daily dosage greater than 200 mg carbidopa is limited.
Current evidence indicates that other standard antiparkinsonism drugs may be continued while Dopicar is being administered, though their dosage may have to be adjusted.
If general anesthesia is required, therapy with Dopicar may be continued as long as the patient is permitted to take fluids and medication orally. If therapy is interrupted temporarily, the usual daily dosage may be administered as soon as the patient is able to take oral medication.
Patients receiving levodopa with another decarboxylase inhibitor: When transferring a patient to Dopicar from levodopa combined with another decarboxylase inhibitor, discontinue dosage at least 12 hours (for instant release formulations) or 24 hours (for sustained release formulations) before Dopicar is started. Begin with a dosage of Dopicar that will provide the same amount of levodopa as contained in the other levodopa/decarboxylase
Patients receiving other antiparkinsonian agents: Current evidence indicates that other antiparkinsonian agents may be continued when Dopicar is introduced, although dosage may have to be adjusted in line with manufacturers
Use in children: The safety of Dopicar in patients under 18 years of age has not been established and its use in patients below the age of 18 is not recommended.
Use in the elderly: There is wide experience in the use of this product in elderly patients. The recommendations set out above reflect the clinical data derived from this experience.
For the relief of symptoms associated with Parkinson’s disease.
Non-selective monoamine oxidase (MAO) inhibitors are contraindicated for use with Dopicar.
These inhibitors must be discontinued at least two weeks before starting Dopicar. Dopicar may be administered concomitantly with the manufacturer’s recommended dose of an MAO inhibitor with selectivity for MAO type B (e.g. selegiline hydrochloride).
Dopicar is contraindicated in patients with narrow-angle glaucoma and in patients with known hypersensitivity to any component of this medication.
Since levodopa may activate a malignant melanoma, it should not be used in patients with suspicious undiagnosed skin lesions or a history of melanoma.
Use in patients with severe psychoses.