What is the dose of Zithromax (azithromycin) using the 200mg/5mL suspension for a 2-year-old child weighing 33.8 pounds?

Azithromycin Dosage for a 2-Year-Old Weighing 33.8 Pounds

The appropriate dose of Zithromax (azithromycin) for a 2-year-old child weighing 33.8 pounds (15.3 kg) using the 200mg/5mL suspension is 30 mg twice daily, which equals 0.75 mL twice daily for 5 days.

Dosage Calculation Based on Weight

According to the FDA-approved drug label for azithromycin 1, the recommended dosing for pediatric patients with common infections follows these guidelines:

For a child weighing 33.8 pounds (15.3 kg):

• This child falls into the "≤15 kg (≤33 lb)" weight category
• The recommended dose is 30 mg twice daily for 5 days

Administration Details:

• Using the 200mg/5mL suspension:
  • 30 mg = (30 ÷ 200) × 5 mL = 0.75 mL
  • Administer 0.75 mL twice daily for 5 days

Dosing Based on Indication

The specific dosing may vary slightly depending on the indication:

1. For community-acquired pneumonia:

   • 10 mg/kg on day 1, followed by 5 mg/kg on days 2-5 1

2. For acute otitis media (ear infection):

   • Option 1: 30 mg/kg as a single dose
   • Option 2: 10 mg/kg once daily for 3 days
   • Option 3: 10 mg/kg on day 1, followed by 5 mg/kg on days 2-5 1

3. For acute bacterial sinusitis:

   • 10 mg/kg once daily for 3 days 1

4. For pharyngitis/tonsillitis:

   • 12 mg/kg once daily for 5 days 1

Important Considerations

• Azithromycin can be taken with or without food 1, though taking it with food may improve gastrointestinal tolerability 2
• Use an appropriate measuring device (oral syringe or medication spoon) for accurate dosing
• Complete the full course of treatment even if symptoms improve before the medication is finished
• The safety of re-dosing azithromycin in pediatric patients who vomit within 30 minutes of receiving a dose has not been well established 1

Clinical Pearls

• Azithromycin has excellent tissue penetration and a long half-life, which allows for once-daily dosing and shorter treatment courses compared to other antibiotics 3
• The drug concentrates in tissues and cells, particularly in leukocytes, monocytes, and macrophages 3
• Gastrointestinal side effects (nausea, diarrhea, abdominal pain) are the most common adverse reactions but are generally milder than with erythromycin 2
• No dosage adjustment is necessary for mild to moderate renal impairment 1

Remember to store the suspension according to the package instructions and shake well before each use.