The aerosol route is attractive for the delivery of mucoactive medications. Mucoactive medications include mucolytics, which depolymerize polymers of mucin (classic mucolytics) or DNA/actin (peptide mucolytics), mucokinetic agents, which increase cough clearance, mucoregulatory medications, which decrease abnormal mucus secretion, and expectorants and ion channel modifiers.
Despite the widespread use of these medications, there are few well conducted studies and thus few data clearly supporting (or failing to support) their use. This will change as our understanding of mucociliary physiology and pharmacology increases and as well designed and well powered clinical trials are conducted with appropriate outcome measurements.
Effective mucoactive therapy should make a profound impact on the care of patients with chronic bronchitis, asthma, cystic fibrosis, and inflammatory airways disease, and will be essential for the effective delivery of gene therapy vectors and bioactive peptides to the airway epithelium.
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