Entacapone is administered orally without regard to meals.
The recommended dosage is 200 mg administered with each levodopa-carbidopa dose up to a maximum of 8 times daily (1.6 g daily). Clinical experience with dosages exceeding 1.6 g daily is limited. Entacapone should be administered only in conjunction with levodopa-carbidopa.
To optimize patient response, reductions in the daily levodopa dosage or frequency of administration may be necessary. In clinical studies, most patients (58%) who were receiving 800 mg or more of levodopa daily or who had moderate or severe dyskinesias before initiating entacapone therapy required a reduction in levodopa dosage; the average reduction in daily levodopa dosage was about 25%.
Entacapone can be administered with conventional tablets, orally disintegrating tablets, or extended-release preparations of levodopa-carbidopa or as a fixed-combination preparation containing levodopa, carbidopa, and entacapone (Stalevo).
The fixed-combination preparation containing levodopa, carbidopa, and entacapone (Stalevo) generally is used in patients receiving stable dosages of levodopa, carbidopa, and entacapone equivalent to those in the combination preparation, but also may be used in certain patients receiving stable dosages of levodopa and carbidopa equivalent to the dosages in the fixed-combination preparation when a decision has been made to add entacapone to the regimen. Tablets containing the fixed combination of levodopa, carbidopa, and entacapone should not be divided, and only one tablet should be administered per dosing interval. Because there is limited clinical experience with entacapone dosages exceeding 1.6 g daily, the maximum dosage of fixed-combination preparations containing levodopa 50-150 mg, carbidopa 12.5-37.5 mg, and entacapone 200 mg (Stalevo 50, 75, 100, 125, and 150) is 8 tablets daily. Because there is limited clinical experience with carbidopa dosages exceeding 300 mg daily, maximum dosage of the fixed-combination preparation containing levodopa 200 mg, carbidopa 50 mg, and entacapone 200 mg (Stalevo 200) is 6 tablets daily.
For patients transferring from therapy with levodopa-carbidopa and entacapone (as separate preparations) to the fixed-combination preparation, recommendations are available for transferring patients currently receiving levodopa-carbidopa preparations containing a 1:4 ratio of carbidopa to levodopa. Patients receiving entacapone 200 mg with each dose of levodopa-carbidopa (e.g., conventional tablet preparation containing 100 mg of levodopa and 25 mg of carbidopa) can be switched to the corresponding strength of the fixed-combination preparation containing levodopa, carbidopa, and entacapone (Stalevo). The manufacturer states that there is no experience to date in transferring patients currently receiving entacapone together with extended-release preparations of levodopa-carbidopa or levodopa-carbidopa preparations containing a 1:10 ratio of carbidopa to levodopa to the fixed-combination preparation.
For patients initiating entacapone therapy, recommendations regarding use of the fixed-combination preparation should be individualized according to the current levodopa dosage and the presence of dyskinesias. For patients treated with levodopa-carbidopa conventional tablets who are receiving more than 600 mg of levodopa daily or who have a history of moderate or severe dyskinesias before initiation of entacapone therapy, dosage should first be adjusted by administering levodopa-carbidopa (1:4 ratio) and entacapone as separate preparations. If it is determined that optimum maintenance dosages of levodopa, carbidopa, and entacapone correspond to the doses in the commercial combination product, the fixed-combination preparation (Stalevo) may be used. For patients receiving levodopa dosages of 600 mg or less daily (conventional tablets, 1:4 ratio) and who do not have dyskinesias, an attempt can be made to initiate therapy with the fixed-combination preparation. The initial dosage of the fixed-combination preparation of levodopa, carbidopa, and entacapone should provide the same dosage of levodopa and carbidopa that the patient currently is taking. However, a reduction in the dosage of levodopa-carbidopa or entacapone may be necessary. Because dosage of levodopa, carbidopa, or entacapone cannot be adjusted individually using the fixed-combination preparation, administration of levodopa-carbidopa and entacapone as separate preparations may be necessary.