What is the recommended dose for Azithromycin (Zithromax) Z Pak?

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From the Guidelines

The recommended dose for Azithromycin (Zithromax) Z Pak is 12 mg per kg once daily, with a maximum dose of 500 mg, for 5 days. This dosage is based on the most recent and highest quality study available, which provides a strong recommendation with moderate quality of evidence 1. The Z Pak is a convenient, oral antibiotic regimen that is effective against a variety of bacterial infections.

  • Key points to consider when prescribing Azithromycin Z Pak include:
    • The medication should be taken orally, with or without food, although taking it with food may help minimize stomach upset.
    • The entire 5-day course should be completed, even if symptoms improve before finishing the medication, to ensure complete eradication of the infection and reduce the risk of antibiotic resistance.
    • Common side effects may include nausea, diarrhea, or abdominal pain, and patients should be advised to report any severe or persistent side effects to their healthcare provider.
  • It's worth noting that the dosage of Azithromycin Z Pak may vary depending on the specific infection being treated and the patient's individual needs, but the recommended dose of 12 mg per kg once daily, with a maximum dose of 500 mg, for 5 days is a commonly used and effective regimen 1.

From the FDA Drug Label

Adults Infection *Recommended Dose/Duration of Therapy *DUE TO THE INDICATED ORGANISMS (See INDICATIONS AND USAGE.) Community-acquired pneumonia (mild severity) Pharyngitis/tonsillitis (second line therapy) Skin/skin structure (uncomplicated) 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5

The recommended dose for Azithromycin (Zithromax) Z Pak is 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5 for adults with community-acquired pneumonia (mild severity), pharyngitis/tonsillitis (second line therapy), or skin/skin structure (uncomplicated) infections 2.

  • Key points:
    • Dose: 500 mg on Day 1, then 250 mg daily on Days 2-5
    • Duration: 5 days
    • Indications: Community-acquired pneumonia, pharyngitis/tonsillitis, skin/skin structure infections

From the Research

Azithromycin Z Pak Dose

The recommended dose for Azithromycin (Zithromax) Z Pak is as follows:

  • A total dose of 1.5 g azithromycin, which can be administered as a three-day regimen (500 mg once daily) or a five-day regimen (500 mg on day 1, followed by 250 mg once daily on days 2 to 5) 3, 4, 5.
  • The 1.5 g total dose is equally effective when administered as a three- or five-day regimen for the treatment of atypical pneumonia 3, 5.
  • A single 1 g oral dose may be effective in the treatment of many sexually transmitted diseases, such as chlamydial infections of the genital tract 4, 6.

Key Points

  • The unique pharmacokinetics of azithromycin are characterized by high, sustained tissue concentrations 4, 7, 6.
  • Tissue concentrations of azithromycin are much higher than serum concentrations, which suggests that proposed standard dosage regimens will produce tissue concentrations above the MICs of relevant pathogens 4, 6.
  • The pharmacokinetics of azithromycin is not significantly altered in elderly subjects and in patients with mild to moderate renal or hepatic insufficiency 7.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Comparison of three-day and five-day courses of azithromycin in the treatment of atypical pneumonia.

European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology, 1991

Research

Selection of dose regimens of azithromycin .

The Journal of antimicrobial chemotherapy, 1993

Research

The pharmacokinetics of azithromycin in human serum and tissues.

The Journal of antimicrobial chemotherapy, 1990

Research

[Clinical pharmacokinetics of azithromycin].

Pathologie-biologie, 1995

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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