Budesonide Budesonide is an anti-inflammatory glucocorticoid steroid that is used for a variety of common ailments. Among conditions related to the respiratory tract, budesonide is used as an inhalational drug for the treatment of asthma, COPD, allergic rhinitis, and nasal polyps. The mechanism of action of budesonide is similar to other corticosteroids and includes a wide range of inhibitory activities against multiple cell types (e.g., mast cells, eosinophils, neutrophils, macrophages and lymphocytes) and mediators (eg, histamine, eicosanoids, leukotrienes, and cytokines) involved in allergic- and non-allergic-mediated inflammation.(AstraZeneca 2000)