What is the treatment for pneumonia?

Treatment of Pneumonia

For community-acquired pneumonia (CAP), treatment should be stratified by severity: mild outpatient CAP requires oral amoxicillin or a macrolide; hospitalized non-severe CAP demands combination therapy with amoxicillin plus a macrolide (clarithromycin or erythromycin); and severe ICU-level CAP requires immediate intravenous broad-spectrum β-lactam (cefuroxime, cefotaxime, or ceftriaxone) plus a macrolide. 1

Outpatient Treatment for Mild CAP

• Oral amoxicillin is the first-line agent for mild CAP, targeting Streptococcus pneumoniae, the most common pathogen 1
• Alternative regimens include macrolides (erythromycin, clarithromycin, or azithromycin) or doxycycline for patients with penicillin allergy or when atypical pathogen coverage is needed 1, 2
• Treatment duration should be 7 days for uncomplicated pneumonia 1
• Fluoroquinolones should not be used as first-line agents in uncomplicated outpatient pneumonia due to resistance concerns 2, 3

Dosing Specifics for Outpatients

• Azithromycin: 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2-5 4
• This regimen can be taken with or without food 4

Hospitalized Non-Severe CAP

• Combined oral therapy with amoxicillin plus a macrolide (erythromycin or clarithromycin) is the preferred regimen for patients requiring hospital admission 2, 1
• The oral route is recommended for non-severe pneumonia unless contraindications exist (e.g., vomiting, severe dysphagia, hemodynamic instability) 2, 1
• When oral treatment is contraindicated, use intravenous ampicillin or benzylpenicillin together with erythromycin or clarithromycin 2

Alternative Regimens for Hospitalized Non-Severe CAP

• A respiratory fluoroquinolone (levofloxacin 750 mg daily or moxifloxacin) may be used as an alternative for patients intolerant of penicillins or macrolides, or where there are local concerns over Clostridium difficile-associated diarrhea 2, 3
• Levofloxacin is currently the only fluoroquinolone with this indication licensed in the UK 2

Severe ICU-Level CAP

• Patients with severe pneumonia must receive immediate parenteral antibiotics upon diagnosis 2, 1
• The preferred regimen is intravenous combination therapy: broad-spectrum β-lactamase stable antibiotic (co-amoxiclav, cefuroxime, cefotaxime, or ceftriaxone) plus a macrolide (clarithromycin or erythromycin) 2, 1
• For patients with risk factors for Pseudomonas aeruginosa (COPD, mechanical ventilation >7 days, prior antibiotics), use antipseudomonal β-lactam (piperacillin-tazobactam or ceftazidime) plus either ciprofloxacin or macrolide plus aminoglycoside 3

Duration for Severe CAP

• For severe microbiologically undefined pneumonia, 10 days of treatment is recommended 2
• Extend treatment to 14-21 days when Legionella, staphylococcal, or Gram-negative enteric bacilli pneumonia are suspected or confirmed 2, 1

Transitioning from IV to Oral Therapy

• Patients initially treated with parenteral antibiotics should be switched to oral therapy when clinical improvement occurs and temperature has been normal for 24 hours, with no contraindication to oral route 2, 1
• The choice of route should be reviewed on the "post-take" round within the first 24 hours and then daily 2
• Ward pharmacists should highlight prescription charts where parenteral treatment continues unnecessarily 2

Management of Treatment Failure

• If patients fail to improve after 48-72 hours, conduct a careful review by an experienced clinician of clinical history, examination, prescription chart, and all investigation results 2, 1
• Order further investigations: repeat chest radiograph, CRP, white blood cell count, and additional microbiological specimens (sputum culture, blood cultures, urinary antigens) 2, 3

Antibiotic Modification for Non-Responders

• For non-severe pneumonia treated with amoxicillin monotherapy, add or substitute a macrolide 2
• For non-severe pneumonia on combination therapy, changing to a fluoroquinolone with effective pneumococcal cover is an option 2
• For severe pneumonia not responding to combination therapy, consider adding rifampicin 2

Hospital-Acquired and Ventilator-Associated Pneumonia (HAP/VAP)

• Empiric therapy should be initiated immediately based on risk factors for specific pathogens and local resistance patterns 2
• The clinical strategy emphasizes prompt empiric therapy for all patients suspected of HAP, as delay in appropriate antibiotic therapy is associated with increased mortality 2
• Gram staining of tracheal aspirates should guide initial empiric therapy, resulting in low incidence of inappropriate treatment 2

VAP-Specific Considerations

• Antibiotic choice should be based on the regimen each patient has received previously, as prior antibiotics strongly predict the etiologic agent 2
• Patients with COPD or >1 week of ventilation should receive combination therapy with antipseudomonal activity 2
• Methicillin-resistant Staphylococcus aureus (MRSA) should not be expected in patients without previous antibiotic therapy, and vancomycin is not warranted in this setting 2
• Vancomycin for MRSA VAP is associated with very poor outcome (≥50% mortality); β-lactams for MSSA have <5% mortality 2

Pathogen-Specific Therapy

When a specific pathogen is identified, targeted therapy should replace empiric treatment:

• For Streptococcus pneumoniae: penicillin G is the drug of choice 1
• For Legionella species: levofloxacin or moxifloxacin (most data for levofloxacin), or macrolide (azithromycin preferred) ± rifampicin 1
• For Mycoplasma pneumoniae or Chlamydophila pneumoniae: macrolide (erythromycin) or doxycycline 200 mg daily 1

Critical Pitfalls to Avoid

• Never use macrolide monotherapy in patients with risk factors for drug-resistant S. pneumoniae (age >65, comorbidities, recent antibiotics, immunosuppression) 3
• Do not continue the same antibiotic regimen beyond 48-72 hours without clinical improvement 3
• Avoid using the same antibiotic class if the patient recently received it 3
• Do not use azithromycin in patients judged inappropriate for oral therapy due to moderate-to-severe illness, cystic fibrosis, nosocomial acquisition, known/suspected bacteremia, hospitalization requirement, elderly/debilitated status, or significant underlying health problems 4
• Antifungal therapy is not required even with Candida colonization in non-neutropenic patients 2

Special Populations

Pediatric Patients

• For community-acquired pneumonia: 10 mg/kg as a single dose on Day 1, followed by 5 mg/kg on Days 2-5 4
• For acute otitis media: 30 mg/kg as a single dose, or 10 mg/kg once daily for 3 days 4

Pregnancy

• For mild pneumonia: oral amoxicillin is first-line 1
• For severe pneumonia: use IV broad-spectrum β-lactamase stable antibiotic (co-amoxiclav, cefuroxime, or ceftriaxone) plus macrolide (clarithromycin or erythromycin) 1

Duration of Therapy

• Treatment duration should generally not exceed 8 days in a responding patient 1
• Uncomplicated S. pneumoniae pneumonia is typically treated for 7-10 days 1
• Patients must be afebrile for 48-72 hours before discontinuing antibiotics 3