What are the choices and duration of oral antibiotics for Community-Acquired Pneumonia (CAP)?

From the Guidelines

For community-acquired pneumonia (CAP), the recommended duration of oral antibiotic therapy is at least 5 days, even if the patient has reached clinical stability before 5 days, as supported by the most recent and highest quality study 1.

Key Considerations

• The choice of oral antibiotic for CAP should be based on the patient's severity of illness, comorbidities, and risk factors for resistant pathogens.
• For most outpatients, amoxicillin 1 gram three times daily is a suitable first-line option.
• In patients with penicillin allergies or in areas with high pneumococcal resistance, doxycycline 100 mg twice daily or a macrolide such as azithromycin 500 mg on day 1 followed by 250 mg daily for 4 more days can be used.
• For patients with comorbidities or risk factors for resistant pathogens, a respiratory fluoroquinolone like levofloxacin 750 mg daily or moxifloxacin 400 mg daily is appropriate.

Duration of Therapy

• The standard duration for CAP treatment is at least 5 days, as recommended by the American Thoracic Society and Infectious Diseases Society of America 1.
• However, a more recent study suggests that short-course antibiotic therapy (≤ 6 days) may be as effective as long-course therapy, with fewer serious adverse events and low mortality 1.
• Patients should be afebrile for 48-72 hours and show clinical improvement before stopping antibiotics.

Special Considerations

• For patients with suspected atypical pathogens, adding a macrolide to beta-lactam therapy is recommended.
• The duration of therapy for CAP due to suspected or proven MRSA or P. aeruginosa should be 7 days, in agreement with recent guidelines 1.
• Further research is needed to determine the optimal duration of therapy for patients with ventilator-associated pneumonia (VAP) and other complex cases.

From the FDA Drug Label

Community-Acquired Pneumonia: 7 to 14 Day Treatment Regimen Adult inpatients and outpatients with a diagnosis of community-acquired bacterial pneumonia were evaluated in 2 pivotal clinical studies In the first study, 590 patients were enrolled in a prospective, multicenter, unblinded randomized trial comparing levofloxacin 500 mg once daily orally or intravenously for 7 to 14 days 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%). Community-Acquired Pneumonia: 5 Day Treatment Regimen To evaluate the safety and efficacy of the higher dose and shorter course of levofloxacin, 528 outpatient and hospitalized adults with clinically and radiologically determined mild to severe community-acquired pneumonia were evaluated in a double-blind, randomized, prospective, multicenter study comparing levofloxacin 750 mg, IV or orally, every day for five days

Choice of Oral Antibiotics for CAP:

• Levofloxacin 500 mg once daily orally for 7 to 14 days
• Levofloxacin 750 mg, IV or orally, every day for five days
• Azithromycin 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5

Duration of Oral Antibiotics for CAP:

• 5 days for azithromycin
• 7 to 14 days for levofloxacin
• 5 days for levofloxacin 750 mg 2

From the Research

Oral Antibiotics for CAP: Choice and Duration

• The choice of oral antibiotics for community-acquired pneumonia (CAP) depends on various factors, including the severity of the disease, patient age, and presence of comorbidities 3, 4, 5.
• A study published in 1998 found that azithromycin was effective in treating CAP in children, with a satisfactory therapeutic outcome similar to those of amoxicillin/clavulanate or erythromycin 3.
• Another study published in 2023 suggested that short treatment durations (7 days or less) may be sufficient for CAP, and clinical criteria can be used to discontinue antibiotic treatment 6.
• A 2014 Cochrane review found that there was no significant difference in the efficacy of various antibiotics for CAP in outpatient settings, but some antibiotics were associated with more adverse events than others 4.
• A 2015 study published in the New England Journal of Medicine found that a strategy of preferred empirical treatment with beta-lactam monotherapy was noninferior to strategies with a beta-lactam-macrolide combination or fluoroquinolone monotherapy with regard to 90-day mortality 5.
• A 2024 study found that broad-spectrum antibiotics were associated with an increased risk of adverse drug events (ADEs) among otherwise healthy adults treated for CAP in the outpatient setting, highlighting the need for antimicrobial stewardship 7.

Duration of Antibiotic Treatment

• The optimal duration of antibiotic treatment for CAP is still under debate, but several studies suggest that short treatment durations (7 days or less) may be sufficient 6, 4.
• A study published in 1998 found that a 5-day course of azithromycin was effective in treating CAP in children 3.
• Another study published in 2023 suggested that clinical criteria can be used to discontinue antibiotic treatment, and that procalcitonin may be a useful marker for determining the duration of treatment 6.

Choice of Antibiotic

• The choice of antibiotic for CAP depends on various factors, including the severity of the disease, patient age, and presence of comorbidities 3, 4, 5.
• Macrolides, such as azithromycin, are commonly used to treat CAP, especially in outpatient settings 3, 4.
• Beta-lactam antibiotics, such as amoxicillin/clavulanate, are also commonly used to treat CAP, especially in hospitalized patients 5.
• Fluoroquinolones, such as levofloxacin, may be used to treat CAP, especially in patients with severe disease or those who are unable to take other antibiotics 4, 5.