title: The expanding armamentarium of drugs to aid sputum clearance: how should they be used to optimize care?
abstract: OBJECTIVE
  This review examines the evidence for use of agents that improve sputum clearance in cystic fibrosis.
  
  
  RESULTS
  The basic defect in cystic fibrosis causes abnormal airway surface liquid leading to mucus plugging and subsequent infection and inflammation in the airways. Agents that improve clearance of secretions should improve lung function, reduce infective exacerbations and may enhance survival. There are two main varieties of mucoactive therapy, namely mucolytic therapy, which reduces viscosity in order to improve clearance, and hyperosmolar therapy, which increases the airway surface liquid volume and increases mucociliary clearance. The development of mannitol as a hyperosmolar agent in dry powder form has heightened the debate regarding the optimal approach to sputum clearance. The evidence for use of individual agents is discussed, as well as a practical approach to combining therapies.
  
  
  CONCLUSIONS
  Dornase alfa, a mucolytic agent, and hypertonic saline and mannitol, both hyperosmolar agents, have all been shown to benefit patients with cystic fibrosis. The optimal combination of therapies has not been identified, but a combination of a hyperosmolar agent combined with a mucolytic provides the most logical approach to improving lung function and reducing exacerbations.
authors.affiliation: aDepartment of Adult Cystic Fibrosis, Royal Brompton Hospital bNational Heart and Lung Institute, Imperial College cDepartment of Physiotherapy, Royal Brompton Hospital, London, UK.
authors.forename: Diana
authors.initials: D
authors.lastname: Bilton
authors.forename: Gemma
authors.initials: G
authors.lastname: Stanford
mesh_terms: D000280:Administration, Inhalation; D003131:Combined Modality Therapy; D003550:Cystic Fibrosis / Q000188:drug therapy* / Q000503:physiopathology; D003850:Deoxyribonuclease I / Q000627:therapeutic use*; D005100:Expectorants / Q000627:therapeutic use*; D006801:Humans; D008353:Mannitol / Q000627:therapeutic use*; D009079:Mucociliary Clearance / Q000187:drug effects*; D009330:Nebulizers and Vaporizers; D026741:Physical Therapy Modalities; D011994:Recombinant Proteins / Q000627:therapeutic use; D012462:Saline Solution, Hypertonic / Q000627:therapeutic use*; D013183:Sputum / Q000187:drug effects*; D016896:Treatment Outcome
chemical_list: D005100:Expectorants; D011994:Recombinant Proteins; D012462:Saline Solution, Hypertonic; D008353:Mannitol; D003850:Deoxyribonuclease I; C568813:dornase alfa