Treatment of Pneumonia
For community-acquired pneumonia (CAP), treatment should be based on patient severity and risk factors, with empiric antibiotic therapy tailored to the most likely pathogens and local resistance patterns. 1
Outpatient Treatment
For healthy adults without comorbidities:
- Amoxicillin 1g three times daily (preferred first-line therapy) 1
- Doxycycline 100mg twice daily (alternative) 1
- Macrolide (azithromycin 500mg on first day then 250mg daily or clarithromycin 500mg twice daily) only in areas with pneumococcal resistance to macrolides <25% 1
For adults with comorbidities (chronic heart, lung, liver, renal disease; diabetes; alcoholism; malignancy; asplenia):
- Combination therapy (preferred): 1
- Amoxicillin/clavulanate (500mg/125mg three times daily, 875mg/125mg twice daily, or 2000mg/125mg twice daily) OR cephalosporin (cefpodoxime 200mg twice daily or cefuroxime 500mg twice daily); AND
- Macrolide (azithromycin or clarithromycin) OR doxycycline 100mg twice daily
- Monotherapy alternative: Respiratory fluoroquinolone (levofloxacin 750mg daily, moxifloxacin 400mg daily) 1, 2
Inpatient Treatment (Non-ICU)
- Combined oral therapy with amoxicillin and a macrolide is preferred 1
- When oral treatment is contraindicated, intravenous ampicillin or benzylpenicillin, together with erythromycin or clarithromycin 1
- Respiratory fluoroquinolones are alternatives for patients intolerant to penicillins or macrolides 1
Severe CAP (ICU or Intermediate Care)
No risk factors for Pseudomonas aeruginosa:
- Non-antipseudomonal third-generation cephalosporin PLUS macrolide 1
- OR moxifloxacin or levofloxacin (with or without non-antipseudomonal cephalosporin) 1
With risk factors for Pseudomonas aeruginosa:
- Antipseudomonal cephalosporin OR acylureidopenicillin/β-lactamase inhibitor OR carbapenem (meropenem preferred) PLUS ciprofloxacin 1
- OR antipseudomonal agent PLUS macrolide AND aminoglycoside 1
Special Considerations
Duration of Treatment:
- Generally should not exceed 8 days in responding patients 1
- Minimum of 5 days, with patient afebrile for 48-72 hours and no more than 1 CAP-associated sign of clinical instability before discontinuation 1, 3
- Short-course therapy (5-7 days) is as effective as extended courses for mild to moderate CAP 3, 4
Route of Administration:
- For ambulatory pneumonia, oral treatment from the beginning 1
- In hospitalized patients, switch from IV to oral when clinically stable 1
- Clinical stability indicators include: resolution of fever, improved respiratory symptoms, hemodynamic stability 1
Aspiration Pneumonia:
- Outpatient/ward: β-lactam/β-lactamase inhibitor, clindamycin, or moxifloxacin 1
- ICU: Clindamycin plus cephalosporin 1
Important Caveats
- Azithromycin is FDA-approved for CAP due to Chlamydia pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, or Streptococcus pneumoniae in patients appropriate for oral therapy 5
- Azithromycin should not be used in patients inappropriate for oral therapy due to moderate to severe illness or risk factors 5
- Monitor for QT prolongation with macrolides, especially in at-risk patients 5
- For patients failing to improve, review clinical history, examination, and consider additional investigations 1
- Early mobilization is recommended for all patients 1
- Low molecular weight heparin should be given to patients with acute respiratory failure 1
- Steroids are not recommended in the routine treatment of pneumonia 1
Treatment Response Assessment
- Monitor response using simple clinical criteria: body temperature, respiratory and hemodynamic parameters 1
- Consider repeat chest radiograph for patients with persistent symptoms or at higher risk of underlying malignancy 1
Remember that local antibiotic resistance patterns should guide empiric therapy choices, and treatment should be adjusted based on microbiological results when available 1.