Effects of mannitol on disorders of mucociliary dysfunction

Mannitol is a hyperosmolar agent and creates an osmolar gradient in the airway after being inhaled, which induces water flux into bronchial lumen. Thereafter, not only periciliary fluid depth is optimized but also mucus is hydrated. This event changes the surface properties of mucus and facilitates mucociliary clearance. When applied to disorders of mucus hypersecretion with impaired mucociliary clearance, it maintains airway hygiene by reducing mucus retention and subsequent mucus plug formation. Then patients' symptoms are eliminated,lung function is improved,bacterial colonization and exacerbation of chronic infection are reduced, and eventually life quality is improved. Therefore, it is considered to be a potential therapy for the disorders. Short-term studies have shown significant clinical outcomes, while long-term efficacy still needs to be approved. Key words: Mannitol;  Inhalational therapy;  Mucus hypersecretion;  Mucociliary clearance