Tobramycin Inhalation

How it works

Tobramycin binds the bacterial 30S ribosomal subunit to inhibit protein synthesis, giving concentration-dependent bactericidal activity against Pseudomonas and other Gram-negative organisms.

Prescribing in practice

• Inhalation can trigger bronchospasm, so the first dose should be supervised with a bronchodilator available and lung function assessed.
• Although systemic absorption is low, caution and consideration of monitoring apply with concurrent or recent systemic aminoglycosides given cumulative oto- and nephrotoxicity risk.
• It is given in intermittent on/off treatment cycles and a bronchodilator may be advised before each dose in reactive airways.

Monitoring

Monitor for bronchospasm and audiometric or renal effects where systemic aminoglycoside exposure is also possible, and review sputum microbiology.

Counselling the patient

• Use any prescribed bronchodilator first and follow the on/off cycle exactly as directed.
• Report new hearing changes, ringing in the ears or dizziness.

Evidence & guidelines

Inhaled tobramycin is supported by cystic fibrosis trial evidence and guideline endorsement for suppressing chronic Pseudomonas infection and preserving lung function.