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Macrolide antibiotic (anti-inflammatory / prophylactic) Pregnancy: Caution — limited data; benefit-risk assessment required.

Azithromycin (COPD Exacerbation Prophylaxis)

Brand names: Zithromax, Azithromycin (generic)

Adult dose

Dose: 250 mg three times per week (Mon/Wed/Fri)
Route: Oral
Frequency: Three times per week (not daily — resistance mitigation)
Max: 250 mg per dose; three doses per week
Long-term prophylaxis for COPD patients with ≥3 exacerbations per year despite optimal inhaled therapy (NICE NG115). Also used in bronchiectasis. Mechanism: anti-inflammatory (immunomodulatory) in addition to bacteriostatic. ALBERT trial: reduces exacerbations by 27%. Must exclude: active TB, hearing impairment (audiology before starting), QTc >450 ms, NTM (non-tuberculous mycobacteria) infection. Annual review.

Paediatric dose

Route: Oral
Frequency: Three times per week
Max: 250 mg per dose
Not standard in paediatric COPD (rare). Used in cystic fibrosis and bronchiectasis in children under specialist guidance.

Dose adjustments

Renal

No dose adjustment required — primarily biliary excretion.

Hepatic

Avoid in severe hepatic impairment.

Clinical pearls

  • ALBERT trial (Albert et al, NEJM 2011): azithromycin 250 mg OD reduces COPD exacerbations by 27% vs placebo in frequent exacerbators — landmark evidence
  • Three times weekly (not daily) dosing used in UK practice to reduce resistance development and GI side effects
  • Pre-treatment checklist (NICE NG115): ECG (QTc), audiology, sputum for TB and NTM, LFTs — do not start without completing
  • Annual hearing assessment mandatory — sensorineural hearing loss can be irreversible
  • Also used in bronchiectasis (BTS bronchiectasis guidelines): 250 mg 3x/week or 500 mg 3x/week depending on Pseudomonas colonisation

Contraindications

  • Active tuberculosis (must exclude with sputum culture before starting)
  • Non-tuberculous mycobacterial (NTM) infection (azithromycin monotherapy promotes macrolide resistance in NTM)
  • QTc >450 ms (men) or >470 ms (women) — QT prolongation risk
  • Significant hearing impairment (sensorineural — ototoxicity risk)
  • Hypersensitivity to macrolides

Side effects

  • GI disturbance (nausea, diarrhoea — less than clarithromycin)
  • QT prolongation (less than clarithromycin but monitor ECG)
  • Sensorineural hearing loss (ototoxicity — check audiology before and annually)
  • Liver enzyme elevation
  • Macrolide antibiotic resistance (prolonged use)

Interactions

  • QT-prolonging drugs (antipsychotics, fluoroquinolones, amiodarone) — additive QT prolongation
  • Warfarin — increases INR; monitor closely
  • Statins (particularly simvastatin) — mild CYP3A4 inhibition; monitor myopathy
  • Digoxin — increased digoxin levels

Monitoring

  • ECG (QTc) — before starting and annually
  • Audiology (before starting and annually)
  • Sputum culture (TB, NTM, Pseudomonas) — before and annually
  • LFTs — baseline and if symptomatic
  • Exacerbation frequency — annual review of ongoing benefit

Reference: BNFc; BNF; NICE NG115 COPD; ALBERT Trial (Albert et al, NEJM 2011); BTS Bronchiectasis Guidelines 2019. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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