Community Acquired Pneumonia

For healthy outpatient adults without comorbidities listed below or risk factors for antibiotic resistant pathogens, American Thoracic Society and Infectious Diseases Society of America recommend:

• 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

• a macrolide (azithromycin 500 mg on first day then 250 mg daily or clarithromycin 500 mg twice daily or clarithromycin extended release 1,000 mg daily) only in areas with pneumococcal resistance to macrolides <25% (conditional recommendation, moderate quality of evidence).

For outpatient adults with comorbidities such as chronic heart, lung, liver, or renal disease; diabetes mellitus; alcoholism; malignancy; or asplenia American Thoracic Society and Infectious Diseases Society of America recommend (in no particular order of preference):

• Combination therapy:

  • amoxicillin/clavulanate 500 mg/125 mg three times daily, or amoxicillin/clavulanate 875 mg/125 mg twice daily, or 2,000 mg/125 mg twice daily, or a cephalosporin (cefpodoxime 200 mg twice daily or cefuroxime 500 mg twice daily); AND

  • macrolide (azithromycin 500 mg on first day then 250 mg daily, clarithromycin [500 mg twice daily or extended release 1,000 mg once daily]) (strong recommendation, moderate quality of evidence for combination therapy), or doxycycline 100 mg twice daily (conditional recommendation, low quality of evidence for combination therapy); OR

• Monotherapy:

  • respiratory fluoroquinolone (levofloxacin 750 mg daily, moxifloxacin 400 mg daily, or gemifloxacin 320 mg daily) (strong recommendation, moderate quality of evidence).

Source: Diagnosis and Treatment of Adults with Community-acquired Pneumonia. An Official Clinical Practice Guideline of the American Thoracic Society and Infectious Diseases Society of America https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST