What is the recommended dose of amoxicillin (amoxicillin) for a child weighing 47 pounds at 90 milligrams per kilogram per day (mg/kg/day)?

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From the Guidelines

For a child weighing 47 pounds (approximately 21.3 kilograms), the recommended dose of amoxicillin at 90 mg/kg/day would be approximately 1,917 mg per day, typically divided into two doses of about 958.5 mg each, given every 12 hours, as per the guidelines outlined in the study by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America 1. This dosing is commonly used for the treatment of community-acquired pneumonia in infants and children older than 3 months of age.

  • The medication should be taken for the full prescribed course, usually 7-10 days, even if symptoms improve before completion.
  • Amoxicillin works by inhibiting bacterial cell wall synthesis, and the 90 mg/kg/day dosing is typically used for more severe infections such as acute otitis media or sinusitis.
  • Always ensure the child takes the medication with food to reduce stomach upset, and complete the entire course to prevent antibiotic resistance.
  • Amoxicillin is commonly available as a suspension (125 mg/5 mL, 200 mg/5 mL, or 400 mg/5 mL) or chewable tablets (125 mg, 200 mg, or 400 mg), so the exact dose may need to be adjusted based on the available formulation. The American Academy of Pediatrics and the American Academy of Family Physicians also recommend a dosage of 80 to 90 mg per kg per day for amoxicillin when used to treat acute otitis media 1. However, the most recent and highest quality study, which is the guideline by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America 1, is used to make this recommendation.

From the FDA Drug Label

Table 1 ... 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours ... 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours

To determine the recommended dose of amoxicillin for a child weighing 47 pounds, first convert the weight to kilograms. 47 pounds is approximately 21.3 kilograms. Given the dose of 90 mg/kg/day, this would be 1917 mg/day for a 21.3 kg child. However, according to the label, the recommended dose is 45 mg/kg/day for severe infections, which would be 958.5 mg/day for a 21.3 kg child, and 25 mg/kg/day for mild/moderate infections, which would be 532.5 mg/day for a 21.3 kg child. Since 90 mg/kg/day is not a recommended dose in the label, and the child's weight is over 40 kg is not applicable as the child weighs 21.3 kg, the dose of 45 mg/kg/day or 25 mg/kg/day should be used, but the 90 mg/kg/day dose is not supported by the label. The FDA label does not answer the question.

From the Research

Dosing Information

  • The recommended dose of amoxicillin for a child is typically based on their weight, with a common dosage being 90 mg/kg/day 2, 3.
  • For a child weighing 47 pounds, we need to convert their weight to kilograms to calculate the dose. Since 1 pound is approximately equal to 0.45 kilograms, a 47-pound child would weigh approximately 21.15 kilograms (47 * 0.45).
  • Using the dosage of 90 mg/kg/day, the total daily dose for a 21.15-kilogram child would be approximately 1903.5 mg (21.15 * 90).
  • This dose is typically divided into two or three doses per day, depending on the specific prescription and the child's needs.

Clinical Efficacy

  • Studies have shown that amoxicillin-clavulanate is effective in treating acute otitis media in children, with success rates ranging from 80% to 90% 2, 4, 5.
  • The efficacy of amoxicillin-clavulanate against specific pathogens, such as Streptococcus pneumoniae and Haemophilus influenzae, has also been demonstrated in clinical trials 2, 4, 5.
  • Comparisons with other antibiotics, such as azithromycin, have shown that amoxicillin-clavulanate can be more effective in certain cases, although the differences may not always be statistically significant 2, 4, 5.

Safety and Tolerability

  • Amoxicillin-clavulanate is generally well-tolerated in children, although gastrointestinal side effects such as diarrhea can occur 3, 6.
  • The incidence of adverse events can vary depending on the specific dosage and duration of treatment, as well as individual patient factors.

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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