What is the treatment for Community-Acquired Pneumonia (CAP)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 4, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Community-acquired pneumonia (CAP) treatment should be guided by the most recent and highest quality evidence, which recommends a minimum of 5 days of antibiotics, with extension of therapy guided by validated measures of clinical stability 1.

Treatment Approach

For outpatient treatment of mild to moderate CAP, the following antibiotics are recommended:

  • Amoxicillin 1g three times daily for 5-7 days as first-line therapy
  • Alternatives include doxycycline 100mg twice daily or azithromycin 500mg on day one followed by 250mg daily for 4 more days For patients with comorbidities or risk factors for drug-resistant pathogens:
  • Amoxicillin-clavulanate 875/125mg twice daily or a respiratory fluoroquinolone like levofloxacin 750mg daily for 5-7 days may be used

Hospitalized Patients

Severe CAP requiring hospitalization typically needs intravenous therapy with:

  • A beta-lactam (ceftriaxone 1-2g daily or ampicillin-sulbactam 1.5-3g every 6 hours) plus a macrolide
  • Or monotherapy with a respiratory fluoroquinolone

Key Considerations

  • Treatment duration is generally 5-7 days for most patients, with longer courses sometimes needed for complicated cases
  • Supportive care including adequate hydration, fever control, and oxygen supplementation if needed is essential
  • Clinical improvement should occur within 48-72 hours; lack of improvement warrants reassessment for complications, resistant organisms, or alternative diagnoses According to the 2019 American Thoracic Society and Infectious Diseases Society of America guideline, initial treatment strategies for inpatients with community-acquired pneumonia should be based on the level of severity and risk for drug resistance 1.

From the FDA Drug Label

Clinical success rates (cure plus improvement) in the clinically evaluable population were 90.9% in the levofloxacin 750 mg group and 91.1% in the levofloxacin 500 mg group. Clinical success (cure plus improvement) with levofloxacin at 5 to 7 days posttherapy, the primary efficacy variable in this study, was superior (95%) to the control group (83%). For both studies, the clinical success rate in patients with atypical pneumonia due to Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila were 96%, 96%, and 70%, respectively.

The treatment of community-acquired pneumonia with levofloxacin has been shown to be effective, with clinical success rates ranging from 90.9% to 95% in different studies 2. The recommended treatment duration is 7 to 14 days, but a 5-day treatment regimen with a higher dose of levofloxacin (750 mg) has also been shown to be effective.

  • Key points:
    • Levofloxacin is effective against community-acquired pneumonia, including cases caused by atypical pathogens.
    • Clinical success rates are high, ranging from 90.9% to 95%.
    • The recommended treatment duration is 7 to 14 days, but a 5-day regimen with a higher dose may also be effective.

From the Research

Treatment Options for Community-Acquired Pneumonia (CAP)

  • The treatment of CAP often involves empirical antibiotic therapy, covering both typical and atypical pathogens 3.
  • Beta-lactams have been considered standard therapy for CAP, but rising resistance rates are a concern 3.
  • For patients with comorbidities or recent antibiotic therapy, combination therapy with a beta-lactam and a macrolide or an antipneumococcal fluoroquinolone alone is recommended 3.
  • Fluoroquinolones, such as moxifloxacin, gatifloxacin, and levofloxacin, have shown high clinical success rates (> 90%) in treating CAP due to S pneumoniae 3.

Comparison of Antibiotic Regimens

  • A study comparing levofloxacin with ceftriaxone and azithromycin for treating CAP found that levofloxacin improved patients' signs and symptoms and reduced hospitalization length, with similar side effects 4.
  • The Infectious Diseases Society of America (IDSA) guidelines recommend initial empiric antimicrobial therapy, with macrolides, doxycycline, and fluoroquinolones suggested for primary empiric therapy 5.

Considerations for Specific Patient Populations

  • For immunocompromised patients with suspected CAP, a consensus statement provides general suggestions for initial treatment, including defining the population, site of care, likely pathogens, microbiologic workup, and empirical therapy for specific pathogens 6.
  • The use of penicillins for treatment of pneumococcal pneumonia is still recommended, as in vitro resistance may not have direct clinical implications 7.

Related Questions

What is the treatment for pneumonia?
What are the alternative antibiotics for Community-Acquired Pneumonia (CAP) in patients allergic to Penicillin (PCN)?
What is the initial treatment recommendation for patients diagnosed with pneumonia?
What antibiotics should be prescribed for an elderly female patient with a history of tobacco use, hypertension (HTN), osteoarthritis, insomnia, and previous lung opacity, diagnosed with influenza A 4 days ago, presenting with shortness of breath (SOB), cough, and night sweats?
What is the best management approach for an elderly nursing home patient with chronic obstructive pulmonary disease (COPD), hypertension (HTN), heart failure (HF), dementia, coronary artery disease (CAD), and cardiomyopathy with a pacemaker, presenting with shortness of breath (SOB), cough, wheezing, and chills, and a chest X-ray (CXR) showing a mild right infrahilar infiltrate and minimal atelectasis, who is allergic to nonsteroidal anti-inflammatory drugs (NSAIDs) and has been started on Mucinex (guaifenesin)?
What is the first line treatment for Diabetic Ketoacidosis (DKA)?
Should I undergo blood tests for parotitis (inflammation of the parotid gland)?
Does semaglutide (Ozempic) lose efficacy on appetite suppression and weight loss at the maximum dose?
What is the role of Tauroursodeoxycholic acid (TUDCA)?
What is the clinical significance of a normal myocardial perfusion study with Lexiscan (regadenoson) and a normal ejection fraction (EF) of 67% with a hypokinetic mid inferolateral segment on echocardiogram?
Can T2 respiratory failure (Type 2 respiratory failure) occur without T1 respiratory failure (Type 1 respiratory failure)?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.