Cefixime Dosing in Pediatric UTI and Other Conditions
For pediatric urinary tract infections, cefixime should be dosed at 8 mg/kg/day, administered either as a single daily dose or divided into two doses (4 mg/kg every 12 hours), with a maximum of 400 mg/day. 1, 2
Standard Pediatric UTI Dosing
- The FDA-approved dosing for children 6 months or older is 8 mg/kg/day for uncomplicated UTIs, which can be given once daily or divided into twice-daily administration 1
- Clinical studies demonstrate excellent efficacy with this regimen, achieving cure rates of 85-94% in pediatric UTI patients 2, 3
- For a practical example, a 10 kg child would receive 80 mg daily (either 80 mg once daily or 40 mg twice daily) 2
Treatment Duration for UTI
- Treat pediatric UTIs for 7-14 days, as shorter courses (1-3 days) have proven inferior for febrile UTIs 4
- The American Academy of Pediatrics specifically recommends against short-course therapy in this population 5
Dosing for Other Pediatric Conditions
Otitis Media
- Use 8 mg/kg/day divided into two doses for acute otitis media 1, 6
- Clinical trials demonstrate 96-100% cure or improvement rates with this regimen 2, 3
- This dosing is comparable in efficacy to cefaclor 20-40 mg/kg/day or amoxicillin 40 mg/kg/day 6
Pharyngitis and Tonsillitis
- Administer 8 mg/kg/day for streptococcal pharyngitis 1
- Studies show effectiveness similar to amoxicillin for acute tonsillitis in pediatric patients 6
Acute Sinusitis
- Use 8 mg/kg/day as a single daily dose for acute sinusitis 3
- Clinical data shows 100% cure or improvement rates in pediatric sinusitis 3
Renal Impairment Adjustments
- For creatinine clearance 21-60 mL/min: reduce dose to 75% of standard (6 mg/kg/day) 1
- For creatinine clearance ≤20 mL/min: reduce dose to 50% of standard (4 mg/kg/day) 1
- These adjustments are critical as cefixime is 20% renally excreted as active drug 7
Important Clinical Considerations
Administration Preferences
- Twice-daily dosing (divided doses) is preferred over once-daily dosing to minimize gastrointestinal adverse effects, particularly diarrhea 7
- Once-daily 400 mg dosing in adults showed higher incidence of GI side effects compared to 200 mg twice daily 7
Spectrum Limitations
- Cefixime has minimal activity against Staphylococcus aureus and no activity against Pseudomonas aeruginosa 6
- For complicated UTIs with gram-positive or non-fermenting organisms, do not initiate cefixime without sensitivity testing 7
- Proteus mirabilis infections may show suboptimal response, particularly in pyelonephritis 7
When to Consider Alternatives
- For toxic-appearing children or those unable to tolerate oral medications, use parenteral ceftriaxone (50-75 mg/kg/day) initially 8, 4
- Switch to oral cefixime once clinical improvement occurs (typically 24-48 hours) 4
- For febrile infants with pyelonephritis, oral cefixime (14 days) is equivalent to 3 days IV cefotaxime followed by oral therapy 5
Common Pitfalls to Avoid
- Do not use cefixime as empiric therapy for complicated UTIs without culture data, as resistant organisms (Enterobacter, Klebsiella) may be present 2
- Avoid once-daily dosing in young children due to increased diarrhea risk 7
- Do not assume efficacy against all Enterobacteriaceae—Enterobacter cloacae and some Klebsiella pneumoniae strains may be resistant 2
- Always adjust for renal function in children with known or suspected renal impairment 1