Inhaled Antibiotics
Ariel Berlinski, MD, FAAP
Introduction
• Inhaled antibiotic therapy with currently available preparations is safe and effective in patients with cystic fibrosis (CF).
• Inhaled antibiotics are sometimes prescribed by pediatric pulmonologists and otolaryngologists for patients without CF who have chronic or recurrent airway infections. However, currently, the only approved indication in the United States is CF.
• Patients with bronchiectasis caused by CF or other etiologic origins (eg, primary ciliary dyskinesia, postinfectious disease) have chronic bacterial colonization with different organisms (eg, Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus [MRSA]) and experience recurrent airway infections.
• Patients with tracheostomies also develop chronic bacterial colonization (eg, P aeruginosa, MRSA) soon after tracheostomy placement and experience recurrent airway infections.
• The inhaled route provides
—High in situ drug concentration
—Reduced systemic drug delivery
—Minimal side effects
• Tobramycin and aztreonam are approved by the U.S. Food and Drug Administration (FDA) for the treatment of P aeruginosa in patients with CF.
• Amikacin, tobramycin, gentamicin, ceftazidime, colistin, vancomycin, and ciprofloxacin are used off-label as inhaled antibiotics. Many of these and more are in development but are not yet approved by the FDA.
Treatment Against P aeruginosa in Patients With CF
• All FDA-approved inhaled antibiotics are drug-device combinations (Figure 110-1).
• Currently approved formulations include
—Tobramycin delivered via nebulizer
▪Treatment lasts 15 minutes
▪Is usually dosed at 300 mg twice daily (28 days “on” and 28 days “off”) with a standard nebulizer
—Tobramycin delivered via dry-powder inhaler
▪Supplied as 28-mg capsules (aluminum-blister packaged)
▪Is usually dosed at 4 capsules twice daily (28 days “on” and 28 days “off”)