Nedocromil is primarily used as a medication to manage and prevent symptoms of asthma. It works by inhibiting the release of inflammatory mediators from various cells involved in allergic reactions, such as mast cells. This helps reduce airway inflammation and prevents bronchoconstriction. It is often prescribed for individuals who experience mild to moderate asthma and is particularly effective in preventing exercise-induced bronchospasm.

Additionally, nedocromil is used to treat allergic conjunctivitis, an eye condition caused by allergens. It helps alleviate symptoms like redness, itching, and watering of the eyes by stabilizing mast cells in the conjunctiva. The medication is typically administered as an eye drop for this purpose.

Nedocromil is also beneficial in managing other allergic conditions, such as seasonal allergies, by reducing the body's hypersensitivity to allergens. It is commonly used as a preventive treatment rather than for acute symptom relief, requiring regular use to achieve optimal results. Its anti-inflammatory properties make it a valuable option for long-term management of chronic allergic and respiratory conditions.