There is evidence from studies in patients with cystic fibrosis that HS can improve mucociliary clearance. The improvement was more impressive in areas that were well ventilated, making it likely that HS will work better in patients with relatively preserved pulmonary function. Newer evidence also suggests that the osmotic effect on the airway surface that was expected to be short lived, may actually persist for longer time periods (up to 8 hours). All these data indicate that HS may be a useful agent in the treatment of CF patients.