Used in combination with levodopa for the treatment of Parkinson’s disease. Enhances the effect of levodopa by inhibiting its peripheral decarboxylation, allowing more levodopa to reach the brain. This reduces the required dose of levodopa and minimizes side effects such as nausea and cardiovascular effects. Particularly effective in managing motor symptoms like tremors, stiffness, and bradykinesia. Also used in the diagnostic testing for Parkinson’s and related disorders.