Cefotaxime Dosage for a 12-Year-Old Child Weighing 47 kg
For a 12-year-old male child weighing 47 kg, the recommended dosage of cefotaxime is 150 mg/kg/day divided into three doses (every 8 hours) administered intravenously, which equals approximately 2.35 grams every 8 hours. 1
Dosage Calculation
The FDA-approved dosing guidelines for cefotaxime provide clear direction for pediatric patients:
- For children weighing less than 50 kg (which includes our 47 kg patient), the recommended daily dose is 50-180 mg/kg divided into four to six equal doses 1
- For moderate to severe infections, the standard dosage is 150 mg/kg/day divided every 8 hours 2, 1
Therefore, the calculation for this 12-year-old child is:
- Daily dose: 47 kg × 150 mg/kg = 7,050 mg (7.05 g) per day
- Divided into three doses: 7,050 mg ÷ 3 = 2,350 mg (2.35 g) every 8 hours
Administration Considerations
- Route of administration: Intravenous (IV) is preferred for moderate to severe infections 1
- Duration: Continue therapy for a minimum of 48-72 hours after the patient defervesces or after evidence of bacterial eradication has been obtained 1
- For infections caused by Group A beta-hemolytic streptococci, a minimum of 10 days of treatment is recommended to prevent rheumatic fever or glomerulonephritis 1
Alternative Dosing Regimens
Some evidence supports alternative dosing regimens that may be considered:
- A twice-daily regimen of 100 mg/kg/day (50 mg/kg every 12 hours) has been studied and shown to be effective for lower respiratory tract infections in pediatric patients 3
- However, the FDA-approved labeling and most recent guidelines still recommend the standard three-times-daily dosing for most infections 1
Clinical Considerations
- For severe infections such as septicemia, higher doses up to 200 mg/kg/day may be required 1
- For suspected penicillin-resistant S. pneumoniae, ensure adequate dosing (150 mg/kg/day) 2
- Monitor renal function, as dose adjustments may be necessary in patients with impaired renal function 1
Common Pitfalls to Avoid
- Underdosing: Using adult fixed doses rather than weight-based dosing in pediatric patients
- Incorrect dosing interval: Using 6-hour intervals when 8-hour intervals are appropriate for the standard 150 mg/kg/day dosage
- Inadequate duration of therapy: Not continuing treatment for at least 48-72 hours after clinical improvement
- Failure to monitor: Not assessing clinical response after 48-72 hours to determine if therapy should be adjusted
By following these guidelines, you can ensure appropriate cefotaxime dosing for this 12-year-old patient while maximizing efficacy and minimizing potential adverse effects.