Cefixime Dosage for a 9-Month-Old Infant Weighing 7.3 kg
For a 9-month-old infant weighing 7.3 kg, administer cefixime 8 mg/kg/day, which equals approximately 58 mg daily, given either as a single daily dose or divided into 4 mg/kg every 12 hours (approximately 29 mg twice daily). 1
Weight-Based Calculation
- The FDA-approved pediatric dosing for cefixime is 8 mg/kg/day for infants 6 months or older 1
- For a 7.3 kg infant: 7.3 kg × 8 mg/kg = 58.4 mg per day 1
- This can be administered as:
- Single daily dose: 58 mg once daily, OR
- Divided dosing: 29 mg every 12 hours 1
Practical Suspension Dosing
Using the 100 mg/5 mL suspension (20 mg/mL concentration):
- Daily dose: 58 mg ÷ 20 mg/mL = 2.9 mL once daily 1
- Divided dose: 29 mg ÷ 20 mg/mL = 1.45 mL every 12 hours 1
According to the FDA dosage chart, infants weighing 7.6 to 10 kg should receive 80 mg/day (4 mL of 100 mg/5 mL suspension), but for a 7.3 kg infant just below this range, 2.5 to 3 mL daily is appropriate 1
Administration Guidelines
- Administer without regard to food 1
- Shake suspension well before each use 1
- Discard unused suspension after 14 days of reconstitution 1
- For infections due to Streptococcus pyogenes, continue treatment for at least 10 days 1
Clinical Monitoring
- Clinical improvement should be evident within 48-72 hours of initiating therapy 2
- If no improvement occurs within this timeframe, reevaluation and consideration of alternative pathogens or resistance is necessary 2
- Cefixime demonstrates excellent efficacy against common pediatric respiratory pathogens including Haemophilus influenzae, Streptococcus pneumoniae, and Streptococcus pyogenes 3, 4
Important Considerations
- Otitis media should be treated with suspension formulation, as clinical trials demonstrated the suspension achieves higher peak blood levels than tablets at equivalent doses 1
- Cefixime has minimal activity against Staphylococcus aureus and is inactive against Pseudomonas aeruginosa, so alternative therapy is required if these pathogens are suspected 3, 5
- The most common adverse effects are diarrhea and stool changes (occurring in up to 20% of patients), which are typically mild, transient, and occur in the first few days of treatment 3, 5
- Divided twice-daily dosing (rather than once-daily) may reduce gastrointestinal adverse effects 6
Contraindications
- Do not use in patients with known allergy to cefixime or other cephalosporins 1