Carbidopa

Carbidopa is an aromatic-L-amino-acid decarboxylase inhibitor with an IC50 of 29 ± 2 μM. It increases the plasma half-life of levodopa from 50 minutes to 1½ hours. CarbiDOPA cannot cross the blood brain barrier, so it inhibits only peripheral DDC. It thus prevents the conversion of L-DOPA to dopamine peripherally. This reduces the side effects caused by dopamine on the periphery,besides, it increases the concentration of L-DOPA and dopamine in the brain.