Cefdinir Dosing for Streptococcal Pharyngitis
For streptococcal pharyngitis, cefdinir is dosed at 14 mg/kg once daily (maximum 600 mg) or 7 mg/kg twice daily (maximum 300 mg per dose) for 10 days in children, and 300 mg twice daily or 600 mg once daily for 10 days in adults and adolescents. 1, 2, 3
Important Context: Cefdinir is NOT First-Line
Cefdinir should only be used in patients with penicillin allergy who cannot tolerate first-generation cephalosporins. 4, 5 Penicillin or amoxicillin remains the drug of choice for strep throat due to proven efficacy, narrow spectrum, safety, and low cost. 4, 6
Specific Dosing Regimens
Pediatric Patients (Ages 1-12 years)
- 14 mg/kg once daily (maximum 600 mg) for 10 days 1, 7
- Alternative: 7 mg/kg twice daily (maximum 300 mg per dose) for 10 days 1, 7
Adults and Adolescents
Critical Treatment Duration
A full 10-day course is essential to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever. 4, 5 While 5-day regimens of cefdinir have shown superior eradication rates compared to 10 days of penicillin in clinical trials 9, the IDSA guidelines do not currently endorse shorter courses for cephalosporins due to insufficient comprehensive evidence. 4
When to Use Cefdinir
Use cefdinir only for patients with non-immediate (non-anaphylactic) penicillin allergy. 4, 5 The treatment algorithm is:
- First-line: Penicillin or amoxicillin 4, 6
- Non-immediate penicillin allergy: First-generation cephalosporins (cephalexin or cefadroxil preferred over cefdinir) 4, 5
- Immediate/anaphylactic penicillin allergy: Clindamycin or azithromycin (avoid ALL cephalosporins including cefdinir due to 10% cross-reactivity risk) 4, 5
Common Pitfalls to Avoid
Do not use cefdinir in patients with immediate hypersensitivity reactions to penicillin (e.g., anaphylaxis, angioedema, urticaria) due to cross-reactivity risk with all beta-lactam antibiotics. 4, 5
Do not prescribe cefdinir as first-line therapy when penicillin or amoxicillin can be used—this unnecessarily broadens antibiotic spectrum and increases cost. 4, 5
Do not shorten the treatment course below 10 days despite clinical improvement, as this increases treatment failure rates and risk of acute rheumatic fever. 4, 5
Efficacy Evidence
Cefdinir demonstrates superior bacteriologic eradication compared to penicillin in clinical trials, with 10-day regimens achieving 91-94% eradication rates versus 70-83% for penicillin. 1, 8, 7 However, this microbiologic superiority does not translate to clinically meaningful differences in symptom resolution or complication prevention, which is why penicillin remains first-line. 4
Tolerability
Diarrhea is more common with cefdinir than penicillin (occurring in approximately 12-13% of patients), though discontinuation rates due to adverse events are generally similar between groups. 2, 8, 7