What are the recommended antibiotic regimens for community-acquired pneumonia?

From the Guidelines

For community-acquired pneumonia, the recommended antibiotic regimens are amoxicillin 1g three times daily, doxycycline 100mg twice daily, or a macrolide such as azithromycin 500mg on day 1, then 250mg daily for 4 more days for healthy outpatients without risk factors. The choice of antibiotic regimen depends on the treatment setting and patient factors, such as comorbidities and recent antibiotic use 1.

Key Considerations

• For outpatients with comorbidities or recent antibiotic use, a respiratory fluoroquinolone (levofloxacin 750mg daily or moxifloxacin 400mg daily) or combination therapy with amoxicillin-clavulanate plus a macrolide is recommended 1.
• For hospitalized non-ICU patients, a beta-lactam (such as ceftriaxone or cefotaxime) plus a macrolide is standard 1.
• For ICU patients, broader coverage with a beta-lactam plus either a macrolide or a respiratory fluoroquinolone is needed 1.

Treatment Duration

• Treatment duration is typically 5-7 days for most patients, extending to 10-14 days for severe cases or certain pathogens 1.

Targeted Pathogens

• These regimens target the most common CAP pathogens, including Streptococcus pneumoniae, Haemophilus influenzae, atypical organisms like Mycoplasma pneumoniae, and respiratory viruses, with broader coverage for patients with risk factors for resistant organisms 1.

From the FDA Drug Label

Levofloxacin tablets are indicated for the treatment of community-acquired pneumonia due to methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae (including multi-drug-resistant Streptococcus pneumoniae [MDRSP]), Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Chlamydophila pneumoniae, Legionella pneumophila, or Mycoplasma pneumoniae Azithromycin tablets are indicated for the treatment of community-acquired pneumonia (mild severity)

The recommended antibiotic regimens for community-acquired pneumonia are:

• Levofloxacin: for the treatment of community-acquired pneumonia due to methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Chlamydophila pneumoniae, Legionella pneumophila, or Mycoplasma pneumoniae
• Azithromycin: for the treatment of community-acquired pneumonia (mild severity) Key points to consider:
• The choice of antibiotic regimen depends on the severity of the pneumonia and the suspected or confirmed causative microorganism.
• Levofloxacin and Azithromycin are two possible options for the treatment of community-acquired pneumonia. 2 3

From the Research

Community-Acquired Pneumonia Microorganisms and Recommended Antibiotic Regimens

• Community-acquired pneumonia (CAP) is a common infection that can be caused by a variety of microorganisms, including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis 4, 5.
• The recommended antibiotic regimens for CAP depend on the severity of the disease, the patient's age and comorbidities, and the likelihood of antibiotic resistance 5, 6.
• For outpatient treatment of CAP, suitable empirical oral antimicrobial agents include a macrolide (e.g., erythromycin, clarithromycin, azithromycin), doxycycline (or tetracycline) for children aged 8 years or older, or an oral beta-lactam with good activity against pneumococci (e.g., cefuroxime axetil, amoxicillin, or a combination of amoxicillin and clavulanate potassium) 5.
• For inpatient treatment of CAP, suitable empirical antimicrobial regimens include an intravenous beta-lactam, such as cefuroxime, ceftriaxone sodium, cefotaxime sodium, or a combination of ampicillin sodium and sulbactam sodium plus a macrolide 5, 7.
• New fluoroquinolones with improved activity against S pneumoniae can also be used to treat adults with CAP, but their use should be limited to patients who have failed other treatments, are allergic to alternative agents, or have a documented infection with highly drug-resistant pneumococci 5.

Specific Antibiotic Regimens

• A combination of a beta-lactam (e.g., ceftriaxone) and a macrolide (e.g., azithromycin) is a recommended regimen for hospitalized patients with CAP 4, 7.
• Monotherapy with a "respiratory quinolone" (e.g., levofloxacin, gatifloxacin, moxifloxacin, or gemifloxacin) is also a recommended regimen for hospitalized patients with CAP 4, 7.
• Ampicillin may be associated with comparable clinical outcomes and lower rates of Clostridioides difficile infection compared to ceftriaxone for patients hospitalized with CAP 8.

Considerations for Antibiotic Resistance

• The increasing prevalence of antibiotic-resistant S pneumoniae strains has important implications for the treatment of CAP 5, 6.
• The use of antibiotics should be guided by susceptibility patterns and the severity of the disease, and alternative agents should be considered for patients with suspected or confirmed antibiotic-resistant infections 5, 6.