What is the appropriate dosage of Amoxicillin for a 9-month-old infant?

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From the Guidelines

The appropriate dosage of Amoxicillin for a 9-month-old infant is 90 mg/kg/day in 2 doses.

Dosage Calculation

To calculate the dosage, we need to know the weight of the infant. Assuming an average weight of 9 kg for a 9-month-old infant, the dosage would be:

  • 90 mg/kg/day x 9 kg = 810 mg/day
  • Divided into 2 doses: 810 mg/day / 2 = 405 mg per dose

Evidence Support

This dosage is supported by the Pediatric Community Pneumonia Guidelines 1, which recommend amoxicillin as the first-line treatment for community-acquired pneumonia in infants and children older than 3 months of age. The guidelines suggest a dosage of 90 mg/kg/day in 2 doses for outpatient treatment of presumed bacterial pneumonia in children under 5 years old 1.

Additional Considerations

The Taiwan treatment guidelines 1 also recommend a similar dosage of 90 mg/kg/day for amoxicillin in children, with a maximum dose of 4000 mg/day. It's essential to note that the dosage may vary depending on the specific diagnosis, severity of the infection, and local susceptibility patterns. Always consult with a healthcare professional for personalized treatment recommendations.

From the FDA Drug Label

2.3 Dosage in Pediatric Patients Aged Less than 12 Weeks (3 months) It is recommended that there be at least 10 days’ treatment for any infection caused by Streptococcus pyogenes to prevent the occurrence of acute rheumatic fever Due to incompletely developed renal function affecting elimination of amoxicillin in this age group, the recommended upper dose of amoxicillin is 30 mg/kg/day divided every 12 hours.

The appropriate dosage of Amoxicillin for a 9-month-old infant is 30 mg/kg/day divided every 12 hours 2.

From the Research

Amoxicillin Dosage for 9-Month-Old Infant

  • The appropriate dosage of Amoxicillin for a 9-month-old infant can be determined based on the child's weight, as recommended by several studies 3, 4, 5.
  • According to the study published in the Journal of Clinical Pharmacology 4, a dosage regimen of 60 mg/kg thrice daily is recommended for infants, as it results in 80.9% of infants achieving their pharmacodynamic target.
  • Another study published in The Pediatric Infectious Disease Journal 6 recommends a high dose of 80 mg/kg/day, divided into three doses, for the treatment of acute otitis media in children.
  • The World Health Organization EML AWaRe Book recommends a higher dose of amoxicillin, given twice daily for five days, for all uncomplicated respiratory infections where an antibiotic is indicated 7.
  • It is essential to note that the dosage should be calculated based on the child's weight, without exceeding the maximum adult dose, and to check the volume of oral liquid required to complete a treatment course to ensure adequate supply 5.
  • The "Rule of Six" (6 mg/lb per dose) can be used as a general guideline for dosing pediatric medications, including amoxicillin, as suggested by the study published in Archives of Family Medicine 3.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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