INHALATION OF DRY-POWDER MANNITOL INCREASES MUCOCILIARY CLEARANCE

Inhalation of hypertonic saline stimulates mucociliary clearance (MCC) in healthy subjects and those with obstructive lung disease, We inves tigated the effect of inhaling the osmotic agent mannitol on MCC. We u sed a dry-powder preparation of mannitol British Pharmacopea (BP) whic h was encapsulated and delivered using a Dinkihaler(TM). MCC was measu red for 75 min in six asthmatic and six healthy subjects on two occasi ons before and after the mannitol inhalation or its control, using Tc- 99m-sulphur colloid and a gamma camera, The inhaled dose of mannitol w as 267+/-171 mg (mean+/-SD) and 400 mg and the percentage fall in forc ed expiratory volume in one second (FEV1) was 22+/-3 and 4+/-2% in the asthmatic and healthy subjects, respectively, The total clearance in the whole right lung for the 60 min from the start of inhalation of ma nnitol was greater by 26.3+/-11.9% in the asthmatic and 18.1+/-4.9% in the healthy subjects compared to the control, The total clearance ove r 75 min was 54.7+/-9.6% and 33.6+/-9.4% on the mannitol and control d ay (p<0.002), respectively. in the asthmatic subjects and 40.5+/-7.1% and 24.8+/-7.8% (p<0.002) in the healthy subjects, In conclusion, inha lation of dry-powder mannitol increases mucociliary clearance in asthm atic and healthy subjects and may benefit patients with abnormal mucoc iliary clearance.