Azithromycin (COPD Exacerbation Prophylaxis)

How it works

It binds the bacterial 50S ribosomal subunit to inhibit protein synthesis, and in this setting is thought to act partly through anti-inflammatory and immunomodulatory effects rather than antibacterial action alone.

Prescribing in practice

• Most important: it prolongs the QT interval and risks serious arrhythmia, so obtain a baseline ECG and review concurrent QT-prolonging drugs before starting long-term use, per MHRA advice.
• Exclude active non-tuberculous mycobacterial infection and consider sputum culture before initiating prophylaxis, as long-term macrolide monotherapy risks driving resistance.
• Reserve for non-smokers or those who have stopped smoking, as the exacerbation benefit is reduced in current smokers; review the indication periodically.

Monitoring

Monitor with baseline and periodic ECG for QT prolongation, liver function, and hearing, and review continued need at intervals.

Counselling the patient

• Report palpitations, fainting, or new hearing problems promptly.
• Tell any prescriber you are taking long-term azithromycin before starting other medicines.

Evidence & guidelines

Long-term macrolide prophylaxis is supported by NICE and trials such as those underpinning reduced COPD exacerbation rates in selected frequent exacerbators.