Treatment of Skin Boil in 8.28 kg Patient
For a skin boil in a patient weighing 8.28 kg, administer oral cephalexin at 25-50 mg/kg/day divided into doses every 6-12 hours for 7-10 days, which translates to approximately 207-414 mg daily (roughly 1-2 teaspoons of 125 mg/5 mL suspension four times daily or 2-4 teaspoons twice daily). 1
Antibiotic Selection and Dosing
The first-line treatment for uncomplicated skin boils (furuncles) in pediatric patients is an oral anti-staphylococcal antibiotic, as most boils are caused by Staphylococcus aureus 2, 3.
Recommended Regimen: Cephalexin (Cefalexin)
- Dosage: 25-50 mg/kg/day in divided doses 1
- For 8.28 kg patient:
- Minimum dose: 207 mg/day (approximately 1 teaspoon of 125 mg/5 mL suspension four times daily)
- Maximum dose: 414 mg/day (approximately 2 teaspoons of 125 mg/5 mL suspension four times daily)
- Alternative: Can divide total daily dose and administer every 12 hours for skin infections 1
- Duration: 7-10 days for skin and soft tissue infections 2
- Preparation: Use 125 mg/5 mL suspension for ease of dosing in this weight range 1
Alternative First-Line Options (if cephalexin unavailable or contraindicated)
- Dicloxacillin: 12 mg/kg/day in 4 divided doses (approximately 100 mg daily for this patient, or 25 mg four times daily) 2
- Clindamycin: 10-20 mg/kg/day in 3 divided doses (approximately 83-166 mg daily, or 28-55 mg three times daily) 2
Clinical Assessment Priorities
Before initiating treatment, evaluate for:
- Severity indicators: Size of boil, presence of surrounding cellulitis, systemic symptoms (fever, irritability), or signs of deeper infection 2, 3
- Need for incision and drainage: Fluctuant boils often require drainage in addition to antibiotics 3
- Risk factors for MRSA: Previous MRSA infection, recent hospitalization, or failure of initial beta-lactam therapy 2
Important Considerations
When to Modify Treatment
If the patient fails to improve within 48-72 hours or if MRSA is suspected or confirmed:
- Switch to clindamycin 10-20 mg/kg/day in 3 divided doses (if local MRSA strains show susceptibility) 2
- Consider trimethoprim-sulfamethoxazole 8-12 mg/kg/day based on trimethoprim component in 2 divided doses 2
- Note: Avoid TMP-SMZ in infants <2 months due to risk of kernicterus 2
Recurrence Prevention
Approximately 10% of patients develop recurrent boils within 12 months 4. For this pediatric patient:
- Ensure complete antibiotic course even if lesion improves 2
- Maintain good hygiene and avoid skin trauma 5, 6
- Monitor for signs of recurrence requiring repeat evaluation 4
Red Flags Requiring Urgent Evaluation
- Rapidly spreading erythema suggesting necrotizing infection 7
- Systemic toxicity (high fever, lethargy, poor feeding) 5
- Peeling skin at pressure points (concerning for staphylococcal scalded skin syndrome) 5
- Failure to respond to appropriate antibiotics within 48-72 hours 3