Azelastine is a popular antihistamine drug used to treat allergic rhinitis and related conditions. Due to its complex chemical structure, it may contain impurities during the manufacturing process. These impurities can affect the purity, safety, and efficacy of the drug. Therefore, it is essential to monitor and control the levels of Azelastine impurities to ensure the quality of the drug. The most common impurities found in Azelastine include related compounds, degradation products, and residual solvents. Proper identification and quantification of these impurities are crucial for ensuring the safety and effectiveness of the drug.