Choosing a nebulizer for cystic fibrosis applications

As the number of inhaled drugs available for cystic fibrosis grows, there is increasing awareness of delivery device issues. Current jet and ultrasonic nebulizers are inefficient at delivering drugs to the lower respiratory tract. There are large differences in output characteristics between nebulizers and high intersubject variability in lung deposition. The clinical effects of inhaled drugs depend on adequate dosing to the lower airway, so we must choose a nebulizer and patient characteristics that will affect lung deposition positively. Aerosols with particle sizes at the smaller end of the respirable range (2 to 3 microns) may enhance the clinical benefit of some drugs, regardless of patient age or disease severity. Breath-enhanced (Venturi) jet nebulizers are less wasteful than constant-output nebulizers and perform better than conventional nebulizers with many drugs. Patient breathing patterns and degree of airway obstruction are important in determining the site of airway deposition. With increased attention to aerosol delivery issues by clinicians, industry, and regulatory agencies, improved technologies will evolve to target therapies to the lung.