Template:Pneumonia Antibiotics

Outpatient

Coverage targeted at S. pneumoniae, H. influenzae, M. pneumoniae, C. pneumoniae, and Legionella

Healthy

No comorbidities (chronic heart, lung, liver, or renal disease; diabetes mellitus; alcoholism; malignancy; or asplenia) and no risk factors for MRSA or Pseudomonas aeruginosa (include prior respiratory isolation of MRSA or P. aeruginosa or recent hospitalization AND receipt of parenteral antibiotics (in the last 90 d))

• Amoxicillin 1 g three times daily (strong recommendation, moderate quality of evidence), OR
• Doxycycline 100 mg twice daily (conditional recommendation, low quality of evidence), OR
• Macrolide in areas with pneumococcal resistance to macrolides <25% (conditional recommendation, moderate quality of evidence).
  • Azithromycin 500 mg on first day then 250 mg daily OR
  • Clarithromycin 500 mg BID or clarithromycin ER 1,000 mg daily
• Duration of therapy 5 days minimum

Unhealthy

If patient has comorbidities or risk factors for MRSA or Pseudomonas aeruginosa

• Combination therapy:
  • Amoxicillin/Clavulanate
    • 500 mg/125 mg TID OR amox/clav 875 mg/125 mg BID OR 2,000 mg/125 mg BID. Duration is for a minimum of 5 days and varies based on disease severity and response to therapy; patients should be afebrile for ≥48 hours and clinically stable before therapy is discontinued
  • OR cephalosporin
    • Cefpodoxime 200 mg BID OR cefuroxime 500 mg BID
  • AND macrolide
    • Azithromycin 500 mg on first day then 250 mg daily
    • OR clarithromycin 500 mg BID OR clarithromycin ER 1,000 mg daily (strong recommendation, moderate quality of evidence for combination therapy)
  • OR doxycycline 100 mg BID (conditional recommendation, low quality of evidence for combination therapy)
• Monotherapy: respiratory fluoroquinolone (strong recommendation, moderate quality of evidence):
  • Levofloxacin 750 mg daily OR
  • Moxifloxacin 400 mg daily OR
  • Gemifloxacin 320 mg daily

Inpatient

• Monotherapy or combination therapy is acceptable
• Combination therapy includes a cephalosporin and macrolide targeting atypicals and Strep Pneumonia
• Adjunctive corticosteroids in severe CAP: The SCCM 2024 Focused Update strongly recommends corticosteroids for hospitalized adults with severe bacterial CAP (strong recommendation, moderate certainty)
  • CAPE COD trial (NEJM 2023): Hydrocortisone 200 mg IV daily (50 mg q6h) in severe CAP requiring ICU/intermediate care → ↓ 28-day mortality (6.2% vs 11.9%, NNT ~18), ↓ intubation, ↓ vasopressor use
  • Duration: 200 mg/day for 4–7 days based on clinical improvement, then tapered (total 8–14 days)
  • Excluded patients already in septic shock
  • No recommendation for or against steroids in less severe CAP
  • Avoid in influenza pneumonia (without bacterial superinfection)
• Duration: Minimum 5 days; continue until clinically stable (temp ≤37.8°C, HR ≤100, RR ≤24, SBP ≥90, SpO2 ≥90% on RA, tolerating PO, baseline mental status) for ≥48 hours
• De-escalation: If empiric MRSA or Pseudomonas coverage was started, de-escalate to standard CAP therapy within 48 hours if cultures/MRSA nasal PCR are negative and patient is improving

Community Acquired (Non-ICU)

Coverage against community acquired organisms plus M. catarrhalis, Klebsiella, S. aureus

• β-lactam (e.g. ceftriaxone 1–2g daily OR ampicillin-sulbactam 1.5–3g q6h OR cefotaxime 1–2g q8h OR ceftaroline 600mg q12h) PLUS
  • Macrolide (e.g. azithromycin 500 mg daily or clarithromycin 500 mg BID) OR
  • Doxycycline 100mg IV/PO BID (if contraindications to both macrolides and fluoroquinolones) OR
• Levofloxacin 750mg IV/PO once daily OR
• Moxifloxacin 400mg IV/PO once daily

ICU, Low Risk of MRSA/Pseudomonas

• Ceftriaxone 1-2g IV + Azithromycin 500mg IV OR
• Ceftriaxone 1-2g IV + (moxifloxacin 400mg IV or levofloxacin 750mg IV)
• Penicillin allergy:
  • (Moxifloxacin or levofloxacin) + (aztreonam 1-2g IV or clindamycin 600mg IV)

ICU, Risk of Pseudomonas (without MRSA risk)

2019 guidelines recommend single antipseudomonal β-lactam (changed from double gram-negative coverage in 2007 guidelines)

• Antipseudomonal β-lactam: Piperacillin-Tazobactam 4.5g q6h OR Cefepime 2g q8h OR meropenem 1g q8h OR Imipenem 500mg q6h
  • PLUS azithromycin 500mg IV daily OR respiratory fluoroquinolone (levofloxacin 750mg IV daily or moxifloxacin 400mg IV daily)
• If Pseudomonas is not isolated and patient is improving, de-escalate to standard CAP regimen

ICU, Risk of MRSA

Add MRSA coverage to appropriate regimen above

• Vancomycin 15–20 mg/kg IV q8-12h (target AUC/MIC 400-600) OR Linezolid 600 mg IV q12h
• MRSA nasal PCR has a high negative predictive value (~95%); if negative, MRSA coverage can be safely discontinued

Hospital Acquired Pneumonia (HAP)

Pneumonia developing ≥48 hours after hospital admission in non-intubated patients

High risk of MRSA or high mortality risk (ventilatory support for HAP or septic shock)

• Antipseudomonal β-lactam from two different classes with activity against Pseudomonas:
  • Piperacillin-Tazobactam 4.5g q6h OR Cefepime 2g q8h OR ceftazidime 2g q8h OR meropenem 1g q8h OR Imipenem 500mg q6h
  • PLUS antipseudomonal non-β-lactam: Levofloxacin 750mg IV q24h OR ciprofloxacin 400mg q8h OR aminoglycoside (e.g. tobramycin, gentamicin, amikacin)
  • PLUS Vancomycin 15-20 mg/kg IV q8-12h OR Linezolid 600mg IV q12h

Low risk of MRSA and low mortality risk

• Single antipseudomonal β-lactam (from list above) may be sufficient
• Of note, the combination of vancomycin + piperacillin-tazobactam carries higher risk of AKI compared to cefepime + vancomycin
• Consider tobramycin or other aminoglycoside in place of fluoroquinolones given FDA 2016 warnings
• Duration: 7 days recommended for HAP/VAP

Ventilator Associated Pneumonia (VAP)

Pneumonia developing ≥48 hours after endotracheal intubation

High risk of MRSA or IV antibiotics in the last 90 days or unit MRSA prevalence >10-20% or unknown

• Include an antibiotic from each of these 3 categories:
  • 1. MRSA coverage: Vancomycin 15-20 mg/kg IV q8-12h OR Linezolid 600 mg IV q12h PLUS
  • 2. Antipseudomonal β-Lactam: Piperacillin-Tazobactam 4.5g q6h OR Cefepime 2g q8h OR meropenem 1g q8h OR Imipenem 500mg q6h OR Aztreonam 2g q8h PLUS
  • 3. Antipseudomonal non-β-Lactam: Ciprofloxacin 400mg IV q8h OR Levofloxacin 750mg IV q24h OR aminoglycoside

Low risk of MRSA and Pseudomonas (no risk factors for antimicrobial resistance, unit MRSA <10-20%)

• Single antipseudomonal β-lactam monotherapy (from list above) is acceptable
• Duration: 7 days recommended

SMW Antibiotic Annotations

This template uses {{AntibioticDose}} to create a single source of truth for antibiotic dosing. Each drug-dose entry simultaneously displays the dose text and creates an SMW subobject linking the antibiotic to this disease page. When a dose is updated in the visible text, the SMW data automatically updates too.