Azelastine is a medication commonly used to treat symptoms of allergic rhinitis (hay fever), such as sneezing, runny or itchy nose, and congestion. It is also used in the treatment of conjunctivitis (inflammation of the eye), particularly when associated with allergic reactions. Azelastine belongs to a class of drugs known as antihistamines and works by blocking histamine, a substance in the body that causes allergic symptoms. Azelastine is typically available as a nasal spray or eye drops and can provide relief from allergy symptoms by reducing inflammation and other allergic reactions.