From the FDA Drug Label
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 recommended dose of Azithromycin for Injection for the treatment of adult patients with pelvic inflammatory disease due to the indicated organisms is: 500 mg as a single daily dose by the intravenous route for one or two days.
The recommended dose of azithromycin (Zithromax) for inpatient treatment is 500 mg as a single daily dose by the intravenous route. The duration of intravenous therapy may vary depending on the specific indication, such as:
- at least two days for community-acquired pneumonia
- one or two days for pelvic inflammatory disease Intravenous therapy should be followed by azithromycin by the oral route to complete a 7 to 10 day course of therapy for community-acquired pneumonia or a 7 day course of therapy for pelvic inflammatory disease 1.
From the Research
The recommended dose of azithromycin (Zithromax) for inpatient treatment is typically 500 mg intravenously once daily for 2-5 days, followed by oral therapy to complete a 7-10 day course if needed. For severe infections, treatment may begin with a loading dose of 500 mg on day 1, followed by 250 mg daily. Dosing should be adjusted for patients with severe renal impairment (GFR <10 mL/min) 2. Azithromycin is a macrolide antibiotic that works by binding to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis. It has excellent tissue penetration and a long half-life, allowing for once-daily dosing. The drug is particularly effective against atypical pathogens like Mycoplasma, Legionella, and Chlamydia, making it valuable for respiratory infections, sexually transmitted infections, and certain skin/soft tissue infections. Some key points to consider when using azithromycin include:
- Monitoring for potential side effects including QT prolongation, hepatotoxicity, and gastrointestinal disturbances 3
- Administering the drug at least 1 hour before or 2 hours after antacids containing aluminum or magnesium to prevent decreased absorption 4
- Being aware of the potential for treatment failures, particularly with macrolide-resistant organisms 5
- Considering the use of azithromycin in combination with other antibiotics, such as beta-lactams, for severe community-acquired pneumonia 2. Overall, azithromycin is a valuable antibiotic for the treatment of various infections, and its use should be guided by the most recent and highest-quality evidence available 2.