Mucolytic Therapy: What,When,Where,Why,and What Is the Evidence?

Abstract

Background:

Mucolytic drugs decrease the viscosity of mucus and sputum, facilitating their removal from the airways through either improved mucociliary clearance or more productive cough. While mucolytics have been used for years in various respiratory diseases in adults and children, clinical trials often do not support their efficacy for improving clinical endpoints such as lung function, exacerbations, and quality of life.

Purpose:

To review the evidence for clinical efficacy of mucolytics in childhood chronic respiratory diseases.

Methods:

Subjective review of systematic reviews and randomized clinical trials of mucolytics (N-acetylcysteine, dornase alpha, and hyperosmolar agents) in children with lung diseases (cystic fibrosis, bronchiectasis, asthma, atelectasis, and bronchiolitis).

Findings:

While all of the mucolytics have shown the ability to decrease the viscosity of mucus and often increase sputum volume acutely, they often do not improve clinical endpoints such as lung function, exacerbations, and reduced hospitalization. Dornase alpha has established short- and long-term clinical efficacy in cystic fibrosis but not other lung diseases. Hypertonic saline has modest short-term efficacy and some long-term efficacy in cystic fibrosis. Evidence is lacking for other mucolytics and the use of any mucolytics in other lung diseases.