What is the recommended dose of amoxicillin (amoxicillin) for a child weighing 70 pounds?

Amoxicillin Dosing for a 70-Pound Child

For a 70-pound (32 kg) child, the recommended amoxicillin dose depends on the indication: for mild to moderate respiratory infections, give 1,440 mg/day divided into two doses (720 mg twice daily), and for severe infections, Group A Streptococcal pharyngitis, or areas with high pneumococcal resistance, give 2,880 mg/day divided into two doses (1,440 mg twice daily, though this exceeds the 1,000 mg per dose maximum for strep throat). 1, 2

Standard Dosing by Indication

Mild to Moderate Respiratory Infections

• The preferred dose is 45 mg/kg/day divided every 12 hours, which equals approximately 720 mg twice daily for a 32 kg child. 1, 2
• This provides adequate coverage for typical respiratory pathogens while minimizing adverse effects. 2
• Treatment duration should be 7-10 days for most respiratory infections, with pneumonia specifically requiring 10 days. 1, 2

Severe Infections or High Pneumococcal Resistance

• For severe respiratory infections or areas with high pneumococcal resistance, use 90 mg/kg/day divided every 12 hours, which equals approximately 1,440 mg twice daily for a 32 kg child. 1, 2
• The maximum daily dose is 4,000 mg per day. 1, 2

Group A Streptococcal Pharyngitis (Strep Throat)

• The Infectious Diseases Society of America recommends 50 mg/kg once daily (maximum 1,000 mg) OR 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days. 3
• For a 32 kg child, this translates to either 1,000 mg once daily OR 500 mg twice daily for 10 days. 3
• Alternative dosing from more recent guidelines suggests 50-75 mg/kg/day divided into 2 doses for 10 days, not exceeding 1,000 mg per dose. 1, 2
• Patients become non-contagious after 24 hours of antibiotic therapy. 2
• The 10-day duration is mandatory to prevent rheumatic fever. 2

Critical Administration Details

• Twice-daily dosing improves adherence compared to three-times-daily regimens, making the every 12-hour schedule the preferred approach. 2
• Every prescription should specify: the total daily dose in mg/kg/day, the number of divided doses per day, the duration of therapy, and the indication for prescription. 2

Monitoring and Follow-Up

• Children on appropriate therapy should demonstrate clinical improvement within 48-72 hours. 1, 2
• If no improvement occurs by 72 hours, reassess the diagnosis and consider alternative antibiotics. 2
• Complete the full prescribed course even if symptoms improve before completion. 1

Common Adverse Effects

• The most common adverse effects are gastrointestinal disturbances including diarrhea, nausea, and vomiting. 1, 2
• Rash, urticaria, and hypersensitivity reactions may occur. 1, 2
• Diarrhea is generally less frequent with twice-daily dosing compared to three-times-daily treatment. 4

Important Clinical Pitfall

• The older recommendation of 40 mg/kg/day in three divided doses is inadequate to effectively eradicate resistant Streptococcus pneumoniae, particularly during viral coinfection. 5
• If MRSA is suspected or confirmed, amoxicillin alone will not be effective and alternative antibiotics must be considered. 2