Cilostazol impurities are the byproducts or substances that are present in cilostazol drug substance or drug product. These impurities can arise from the manufacturing process, storage, or degradation of the drug. It is essential to control the levels of impurities in cilostazol as these can affect the safety and efficacy of the drug. Regulatory guidelines set limits for specific impurities, and analytical methods are developed to detect and quantify them. Manufacturers need to ensure the quality of cilostazol by monitoring impurities throughout the drug's life cycle.