What are the doses of ceftriaxone (Ceftin) and azithromycin for treating community-acquired pneumonia (CAP)?

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From the Guidelines

For community-acquired pneumonia (CAP), the recommended doses are ceftriaxone 1-2 grams intravenously once daily plus azithromycin 500 mg orally or intravenously once daily. The choice of ceftriaxone and azithromycin is based on the guidelines from the Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults 1. Some key points to consider when treating CAP include:

  • The typical duration of therapy is 5-7 days, with consideration for longer treatment in more severe cases.
  • Patients can be switched from intravenous to oral therapy when they show clinical improvement, are hemodynamically stable, and can tolerate oral medications.
  • For oral step-down therapy, amoxicillin-clavulanate or a respiratory fluoroquinolone may be used.
  • This combination therapy targets both typical bacterial pathogens (with ceftriaxone) and atypical pathogens like Mycoplasma and Legionella (with azithromycin).
  • The dual coverage is particularly important for hospitalized patients with CAP, as it addresses the broad spectrum of potential causative organisms and has been shown to reduce mortality compared to monotherapy 1. It's also important to note that the guidelines recommend against using monotherapy with a macrolide for patients with a significant risk of DRSP infection, and instead recommend combination therapy with a b-lactam effective against S. pneumoniae plus a macrolide 1. In terms of specific dosing, ceftriaxone is typically given at a dose of 1-2 grams intravenously once daily, while azithromycin is given at a dose of 500 mg orally or intravenously once daily 1. Overall, the combination of ceftriaxone and azithromycin is a recommended regimen for the treatment of CAP, particularly for hospitalized patients or those with a high risk of DRSP infection.

From the FDA Drug Label

Community-acquired pneumonia (mild severity) 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5 The recommended dose of Azithromycin for Injection for the treatment of adult patients with community-acquired pneumonia due to the indicated organisms is: 500 mg as a single daily dose by the intravenous route for at least two days

The dose of azithromycin for treating community-acquired pneumonia (CAP) is 500 mg on Day 1, followed by 250 mg once daily on Days 2 through 5 for oral administration, or 500 mg as a single daily dose by the intravenous route for at least two days, followed by oral therapy to complete a 7 to 10 day course of therapy. There is no information about the dose of ceftriaxone (Ceftin) in the provided drug labels. 2 3

From the Research

Doses for Ceftin and Azithromycin

  • The doses of ceftriaxone (Ceftin) and azithromycin for treating community-acquired pneumonia (CAP) are not explicitly stated in the provided studies, but the combination of ceftriaxone and azithromycin is mentioned as a treatment option 4.

Treatment Duration

  • Hospitalized patients without risk factors for resistant bacteria can be treated with β-lactam/macrolide combination therapy, such as ceftriaxone combined with azithromycin, for a minimum of 3 days 4.

Comparison of Azithromycin and Doxycycline

  • Azithromycin was associated with a lower mortality and more hospital-free days compared to doxycycline in combination with beta-lactams in hospitalized patients with CAP 5.

Comparison of Levofloxacin and Ceftriaxone plus Azithromycin

  • Monotherapy with oral Levofloxacin was as effective as treatment with Ceftriaxone plus Azithromycin combination in patients with CAP who required hospitalization 6.

Specific Dosing Information

  • One study mentions that Ceftriaxone 1gr BD, plus oral Azithromycin (250 mg, once daily) for seven to ten days was used as a standard regimen 6.
  • Another study mentions that a 3-day course of azithromycin was used in combination with ceftriaxone 7.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Is azithromycin the first-choice macrolide for treatment of community-acquired pneumonia?

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2003

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.

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