Benserazide is a drug used in the treatment of Parkinson's disease. It acts as a dopa decarboxylase inhibitor, which helps to increase the effectiveness of levodopa, another medication commonly used in the treatment of Parkinson's. Benserazide impurities are unwanted substances that may be present in the drug, which can affect its purity, quality, and efficacy. It is important to identify and control these impurities to ensure the safety and effectiveness of the medication.