Antihistamine nasal sprays are medications designed to relieve allergy symptoms, such as a runny or itchy nose. They work by blocking the action of histamine, a substance in the body that causes allergic reactions. These sprays are often used for conditions like hay fever and can provide quick relief from nasal congestion and sneezing. These sprays are typically easy to use and can be found over-the-counter or by prescription. Common active ingredients include azelastine and olopatadine. Users should follow the instructions carefully to ensure effective treatment and minimize potential side effects, such as drowsiness or nasal irritation.