What is the appropriate dose of cefixime (cephalosporin antibiotic) for a 4-year-old patient weighing 13.5-15 kg given 2.5 mL of cefixime syrup with a concentration of 100mg/5mL?

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Cefixime Dose Calculation for 4-Year-Old Child

The patient is receiving 50 mg of cefixime per dose (2.5 mL × 100 mg/5 mL = 50 mg), which translates to approximately 3.3-3.7 mg/kg/day if given once daily, or 6.6-7.4 mg/kg/day if given twice daily—both significantly below the recommended 8 mg/kg/day dosing for pediatric patients. 1

Recommended Dosing

  • The FDA-approved dose for pediatric patients 6 months or older is 8 mg/kg/day of cefixime suspension, which may be administered as a single daily dose or divided into two doses of 4 mg/kg every 12 hours. 1

  • For a child weighing 13.5-15 kg, the correct total daily dose should be:

    • 13.5 kg patient: 108 mg/day (5.4 mL of 100 mg/5 mL suspension once daily, or 2.7 mL twice daily) 1
    • 15 kg patient: 120 mg/day (6 mL of 100 mg/5 mL suspension once daily, or 3 mL twice daily) 1

Current Dose Assessment

  • The current prescription of 2.5 mL of 100 mg/5 mL concentration delivers only 50 mg per dose 1
  • If this is being given once daily, the patient receives only 50 mg/day (3.3-3.7 mg/kg/day)
  • If given twice daily, the patient receives 100 mg/day (6.6-7.4 mg/kg/day)—still below the recommended 8 mg/kg/day 1

Clinical Implications

  • Underdosing may lead to treatment failure and development of antibiotic resistance, particularly problematic given cefixime's role in treating respiratory and urinary tract infections. 2, 3

  • Clinical trials demonstrating cefixime's efficacy in pediatric otitis media and respiratory infections used the standard 8 mg/kg/day dosing regimen. 4

  • The dose should be corrected to approximately 5.4-6 mL once daily (or 2.7-3 mL twice daily) of the 100 mg/5 mL suspension to achieve the therapeutic target of 8 mg/kg/day. 1

Dosing Frequency Considerations

  • While cefixime's 3-hour half-life permits once-daily dosing for many infections, the FDA label allows flexibility for either once-daily or twice-daily administration. 1, 2

  • For otitis media specifically, clinical trials used the suspension formulation, as it achieves higher peak blood levels than tablets at equivalent doses. 1

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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