Cromolyn is primarily used as a mast cell stabilizer to prevent the release of histamine and other inflammatory mediators. It is commonly applied in the management of allergic conditions such as asthma, allergic rhinitis, and conjunctivitis. In asthma, it is administered via inhalation to reduce airway inflammation and prevent asthma attacks triggered by allergens or exercise. For allergic rhinitis, it is used as a nasal spray to alleviate symptoms like sneezing, itching, and runny nose. In eye drop form, it helps relieve itching and redness caused by allergic conjunctivitis. Additionally, cromolyn is sometimes used off-label to manage mastocytosis, a condition involving excessive mast cell activation. Its preventive nature makes it most effective when used consistently before exposure to allergens.