If levodopa is administered alone, it isextensively metabolized by decarboxylase inthe liver, kidney, and gastrointestinal tract.To prevent this peripheralmetabolism.levodopa is coadministered with carbidopa,a peripheral decarboxylase inhibitor. Thecombination of levodopa with carbidopalowers the necessary dose of levodopa andreduces peripheral side effects associatedwith its administration
If levodopa is administered alone, it is extensively metabolized by decarboxylase in the liver, kidney, and gastrointestinal tract. To prevent this peripheral metabolism. levodopa is coadministered with carbidopa, a peripheral decarboxylase inhibitor. The combination of levodopa with carbidopa lowers the necessary dose of levodopa and reduces peripheral side effects associated with its administration
L-dopaFate of administeredoralL-dopa plus carbidopa90%levodopaismetabolizedRemain10%L-dopaIntolevodopaCNSDopa decarboxylasePeripheraldecarboxylaseDopamineDopainhibitordecarboxylaseDopamine
L-dopa oral 90% levodopa is metabolized Dopa decarboxylase Dopamine Dopa decarboxylase Dopamine L-dopa Into CNS Remain 10% levodopa Fate of administered L-dopa plus carbidopa Peripheral decarboxylase inhibitor (-)