What is the dosage and treatment duration of azithromycin for various bacterial infections?

From the Guidelines

Azithromycin dosing and treatment duration vary by infection type, with a single 1g dose often used for gonococcal and chlamydia infections, while non-gonococcal infections may be treated with 500mg on day 1 followed by 250mg for 4 days, as recommended by the European Association of Urology guidelines 1. The dosage and treatment duration of azithromycin for various bacterial infections are as follows:

• For gonococcal infection, azithromycin can be used as a single 1g dose, or in cases of cephalosporin allergy, 2g can be used in combination with gentamicin or gemifloxacin 1.
• For non-gonococcal infection, azithromycin can be used at a dose of 500mg on day 1, followed by 250mg for 4 days, as an alternative to doxycycline 1.
• For chlamydia trachomatis, azithromycin can be used as a single 1.0-1.5g dose, or doxycycline can be used at a dose of 100mg twice daily for 7 days 1.
• For mycoplasma genitalium, azithromycin can be used at a dose of 500mg on day 1, but in cases of macrolide resistance, moxifloxacin may be substituted 1.
• For ureaplasma urealyticum, doxycycline is the preferred treatment, but azithromycin can be used as a single 1.0-1.5g dose 1. It is essential to note that the treatment duration is typically short (1-5 days) due to azithromycin's long half-life and persistence in tissues, allowing it to maintain therapeutic levels for extended periods after dosing ends, as seen in other contexts 1. Key considerations for azithromycin use include:
• Administration on an empty stomach, 1 hour before or 2 hours after meals
• Completion of the full treatment course, even if symptoms improve
• Caution in patients with liver or kidney disease
• Potential concern for QT interval prolongation, especially in patients with cardiac conditions, although this is not explicitly mentioned in the provided guidelines 1.

From the FDA Drug Label

DOSAGE & ADMINISTRATION SECTION 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 Acute bacterial exacerbations of chronic obstructive pulmonary disease (mild to moderate) 500 mg QD × 3 days OR 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5 Acute bacterial sinusitis500 mg QD × 3 days Genital ulcer disease (chancroid)One single 1 gram dose Non-gonoccocal urethritis and cervicitisOne single 1 gram dose Gonococcal urethritis and cervicitisOne single 2 gram dose

The dosage and treatment duration of azithromycin for various bacterial infections are as follows:

• 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
• Pharyngitis/tonsillitis (second line therapy): 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5
• Skin/skin structure (uncomplicated): 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5
• Acute bacterial exacerbations of chronic obstructive pulmonary disease (mild to moderate): 500 mg QD × 3 days OR 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5
• Acute bacterial sinusitis: 500 mg QD × 3 days
• Genital ulcer disease (chancroid): One single 1 gram dose
• Non-gonoccocal urethritis and cervicitis: One single 1 gram dose
• Gonococcal urethritis and cervicitis: One single 2 gram dose Key points to note:
• The dosage and treatment duration may vary depending on the specific infection and patient population (e.g., pediatric patients) 2
• Azithromycin can be taken with or without food
• No dosage adjustment is recommended for subjects with renal impairment (GFR ≤80 mL/min), but caution should be exercised when administering to subjects with severe renal impairment 2

From the Research

Dosage and Treatment Duration of Azithromycin

The dosage and treatment duration of azithromycin vary depending on the type of bacterial infection being treated.

• For community-acquired pneumonia, a 5-day course of azithromycin has been shown to be effective in children 3.
• For uncomplicated genital chlamydial infections, a single 1 g oral dose of azithromycin has been shown to be effective 4.
• For respiratory tract infections, a 3-day oral regimen of once-daily azithromycin has been shown to be as effective as 5- to 10-day courses of other antibacterial agents 5.

Specific Infections and Treatment Durations

• Uncomplicated urethritis/cervicitis associated with N. gonorrhoeae, Chlamydia trachomatis, or U. urealyticum: a single dose azithromycin regimen offers a distinct advantage over currently available pharmacological options 6.
• Early Lyme disease: azithromycin has been shown to be effective in the treatment of early Lyme disease 6.
• Acute exacerbations of chronic bronchitis: azithromycin is of equivalent efficacy to amoxicillin in the treatment of such patients 6.

Pharmacokinetics and Tissue Concentrations

• Azithromycin is rapidly and highly concentrated in a number of cell types after absorption, including leucocytes, monocytes, and macrophages 5.
• The drug undergoes extensive distribution into tissue, from where it is subsequently eliminated slowly 5.
• Tissue concentrations of azithromycin are more important than those in serum when treating respiratory and other infections 6.