Common organisms
- • Strep pneumoniae
- • Mycoplasma
- • Chlamydia pneumoniae
- • Legionella
- • H. influenzae
Empirical therapy
- • Outpatient: Amoxicillin 1 g PO TDS ± Azithromycin
- • Inpatient ward: Ceftriaxone 1-2 g IV OD + Azithromycin 500 mg IV/PO OD
- • ICU: Ceftriaxone + Azithromycin OR Levofloxacin
Culture-directed
- • Pen-sensitive S. pneumoniae: Amoxicillin
- • Legionella: Azithromycin or Levofloxacin
Adverse effects
- • β-lactam allergy
- • QT prolongation with macrolides/fluoroquinolones
- • C. difficile risk
Monitoring
- • CURB-65 / response by 48-72h
- • Repeat CXR if not improving
Clinical pearls
- • De-escalate by 48-72h once cultures available
- • 5-day course usually adequate
Educational support only — follow local antibiogram and institutional protocols.
