Cefadroxil Dosing for Pediatric Strep Throat
For children with streptococcal pharyngitis, give cefadroxil 30 mg/kg once daily (maximum 1 gram) for 10 days, using either the 250 mg/5 mL or 500 mg/5 mL oral suspension concentration 1, 2.
Weight-Based Dosing Table
The FDA-approved dosing chart provides practical guidance 2:
Using 250 mg/5 mL concentration:
- 10 lbs (4.5 kg): ½ teaspoon daily
- 20 lbs (9.1 kg): 1 teaspoon daily
- 30 lbs (13.6 kg): 1½ teaspoons daily
- 40 lbs (18.2 kg): 2 teaspoons daily
- 50 lbs (22.7 kg): 2½ teaspoons daily
- 60 lbs (27.3 kg): 3 teaspoons daily
Using 500 mg/5 mL concentration:
- 40 lbs (18.2 kg): 1 teaspoon daily
- 50 lbs (22.7 kg): 1¼ teaspoons daily
- 60 lbs (27.3 kg): 1½ teaspoons daily
- ≥70 lbs (31.8 kg): 2 teaspoons daily
Concentration Selection
Choose the 500 mg/5 mL concentration for children ≥40 lbs to reduce volume and improve compliance. Use the 250 mg/5 mL concentration for smaller children (<40 lbs) for more precise dosing 2.
Key Clinical Points
Guideline Support
The IDSA 2012 guidelines specifically endorse cefadroxil at 30 mg/kg once daily (max 1 g) for 10 days as a strong recommendation with high-quality evidence for penicillin-allergic patients (avoiding those with immediate-type hypersensitivity) 1. This once-daily regimen significantly improves compliance compared to multiple daily dosing schedules.
Administration Details
- Give without regard to meals, though administering with food may reduce GI upset 2
- Reconstitute properly: Add specified water volume in two portions, shake well after each addition
- Refrigerate after reconstitution and discard after 14 days 2
- Shake well before each use
Clinical Efficacy
Research demonstrates cefadroxil achieves 90-100% bacterial eradication rates in pediatric strep pharyngitis, comparable or superior to penicillin 3, 4. The once-daily dosing achieves significantly better compliance (>90%) than three-times-daily penicillin regimens 5. Throat cultures typically turn negative within 18-24 hours of starting therapy 6, 3.
Common Pitfalls to Avoid
- Don't underdose: Always calculate the full 30 mg/kg, up to the 1 gram maximum
- Don't shorten duration: Complete the full 10-day course to prevent rheumatic fever and ensure bacterial eradication 1, 2
- Don't use in immediate penicillin allergy: Cephalosporins carry cross-reactivity risk in patients with anaphylaxis to penicillin 1
- Don't forget to refrigerate: Reconstituted suspension degrades at room temperature
When to Reassess
Reevaluate patients with worsening symptoms after starting antibiotics or symptoms persisting beyond 5 days of treatment 7.