Azithromycin Dosing for a 5-Year-Old Child Weighing 48 Pounds
For a 5-year-old male weighing 48 pounds (approximately 22 kg), the recommended dose of azithromycin for community-acquired pneumonia is 10 mg/kg (220 mg) on day 1, followed by 5 mg/kg (110 mg) once daily on days 2-5. 1
Dosing Calculation
- Weight conversion: 48 pounds = 21.8 kg (rounded to 22 kg)
- Day 1 dose: 10 mg/kg × 22 kg = 220 mg
- Days 2-5 dose: 5 mg/kg × 22 kg = 110 mg per day
Administration Options
Based on the FDA-approved drug label, there are two concentration options for the oral suspension:
Using 200 mg/5 mL suspension:
- Day 1: 5.5 mL (approximately 1 teaspoon + ½ teaspoon)
- Days 2-5: 2.75 mL (approximately ½ teaspoon + ¼ teaspoon)
Using 100 mg/5 mL suspension:
- Day 1: 11 mL (approximately 2 teaspoons + 1 teaspoon)
- Days 2-5: 5.5 mL (approximately 1 teaspoon + ½ teaspoon)
Clinical Context
This dosing regimen is specifically indicated for community-acquired pneumonia in pediatric patients and aligns with the recommendations from the Infectious Diseases Society of America (IDSA) and the Pediatric Infectious Diseases Society (PIDS) guidelines 2.
The 5-day regimen is the standard of care for azithromycin treatment of community-acquired pneumonia in children, as it provides adequate tissue concentrations due to azithromycin's long half-life and excellent tissue penetration.
Important Considerations
- Azithromycin can be taken with or without food 1
- Monitor for potential side effects, primarily gastrointestinal (abdominal pain, diarrhea, nausea, vomiting)
- Clinical improvement should be seen within 48-72 hours; if not, reevaluation is necessary 2
- For children with presumed atypical pneumonia, azithromycin is the first-line agent 2, 3
Common Pitfalls to Avoid
- Using adult dosing in pediatric patients
- Inadequate duration of therapy (the full 5-day course should be completed even if symptoms improve)
- Failure to reassess after 48-72 hours if no clinical improvement is observed
- Not considering local resistance patterns when selecting empiric therapy
By following this evidence-based dosing regimen, you can provide effective treatment for community-acquired pneumonia while minimizing the risk of adverse effects and antimicrobial resistance.