Used primarily as an antihistamine in ophthalmic solutions to treat symptoms of allergic conjunctivitis. It helps reduce itching, redness, and swelling of the eyes caused by allergic reactions. Emedastine works by blocking histamine H1 receptors locally in the eye, preventing the action of histamine released during an allergic response. Due to its topical application and rapid onset, it is commonly prescribed for short-term relief in seasonal and perennial allergic eye conditions.