Manidipine is a calcium channel blocker used to treat high blood pressure. However, the drug may contain impurities that can affect its effectiveness and safety. These impurities can arise during the manufacturing process or storage of the drug. Some of the known impurities in Manidipine include degradation products, residual solvents, and heavy metals. It is important to monitor the levels of these impurities to ensure the drug is safe for use.