Is cefdinir safe for a 6‑month‑old infant and what is the appropriate pediatric dosage?

Cefdinir Safety and Dosing for a 6-Month-Old Infant

Cefdinir is FDA-approved and safe for infants ≥6 months of age, with a standard pediatric dose of 14 mg/kg/day administered either as 7 mg/kg every 12 hours or 14 mg/kg once daily for most infections. 1

FDA-Approved Dosing by Indication

For acute bacterial otitis media:

• 7 mg/kg every 12 hours for 5–10 days, or
• 14 mg/kg once daily for 10 days 1

For acute maxillary sinusitis:

• 7 mg/kg every 12 hours for 10 days, or
• 14 mg/kg once daily for 10 days 1

For pharyngitis/tonsillitis:

• 7 mg/kg every 12 hours for 5–10 days, or
• 14 mg/kg once daily for 10 days 1

For uncomplicated skin and skin structure infections:

• 7 mg/kg every 12 hours for 10 days (once-daily dosing has not been studied for skin infections) 1

Clinical Context and Appropriate Use

Cefdinir is NOT a first-line agent for most pediatric infections. For community-acquired pneumonia in infants and children >3 months, high-dose amoxicillin (90 mg/kg/day in 2 doses) remains the definitive first-line therapy because it provides superior coverage of Streptococcus pneumoniae, including penicillin-resistant strains. 2, 3

Cefdinir is an acceptable alternative in specific scenarios:

• Non-severe penicillin allergy (when cephalosporin cross-reactivity risk is acceptable) 3
• Step-down oral therapy after initial parenteral treatment 3
• Infections caused by β-lactamase-producing Haemophilus influenzae or Moraxella catarrhalis 4, 5
• Children who are not fully immunized against H. influenzae type b 3

Important Limitations and Pitfalls

Cefdinir lacks adequate activity against penicillin-resistant S. pneumoniae (MIC ≥2 µg/mL). Even at the higher 25 mg/kg/day dose, pharmacodynamic studies demonstrate that cefdinir achieves bactericidal concentrations for <40% of the dosing interval against penicillin-nonsusceptible strains, making it ineffective for resistant pneumococcal infections. 6

Do not use cefdinir as empiric monotherapy for:

• Suspected pneumococcal pneumonia in areas with high penicillin resistance 2, 3
• Severe pneumonia requiring hospitalization 2, 3
• Infections where MRSA is a consideration (cefdinir has no MRSA activity) 3

Administration and Drug Interactions

Cefdinir oral suspension may be administered without regard to meals. 1

Critical drug interactions to avoid:

• Administer cefdinir at least 2 hours before or after iron supplements, as iron forms a nonabsorbable complex that reduces cefdinir absorption 1
• Iron-fortified infant formula (2.2 mg elemental iron/6 oz) does not significantly affect cefdinir pharmacokinetics and may be given concurrently 1
• Avoid highly iron-fortified breakfast cereals around dosing times 1

Reddish stools may occur due to cefdinir-iron complexes in the gastrointestinal tract; this is benign and does not indicate bleeding. 1

Safety Profile

Cefdinir is generally well tolerated in infants ≥6 months. Diarrhea is the most common adverse event, occurring in approximately 20% of pediatric patients receiving higher doses. 7, 6, 8 In comparative trials, overall adverse event rates with cefdinir once-daily dosing were statistically lower than with amoxicillin-clavulanate. 7, 8

The oral suspension has demonstrated superior taste and palatability compared to other oral antimicrobials, which may improve adherence in young children. 4, 5

Practical Dosing Example for a 6-Month-Old

For a 9 kg (20 lb) infant:

• 7 mg/kg twice daily: 2.5 mL of 125 mg/5 mL suspension every 12 hours 1
• 14 mg/kg once daily: 5 mL of 125 mg/5 mL suspension once daily 1

After reconstitution, the suspension remains stable for 10 days at room temperature (25°C/77°F); discard any unused portion after 10 days. 1

When to Choose Cefdinir Over First-Line Agents

Consider cefdinir for a 6-month-old when:

• The infant has a documented non-severe penicillin allergy and requires treatment for acute otitis media or sinusitis 3
• Amoxicillin has failed after 48–72 hours and β-lactamase-producing organisms are suspected 3
• The infant is not fully immunized and requires broader coverage for H. influenzae 3

Do not use cefdinir when:

• High-dose amoxicillin (90 mg/kg/day) is appropriate and tolerated 2, 3
• Penicillin-resistant S. pneumoniae is likely (use amoxicillin-clavulanate or parenteral ceftriaxone instead) 2, 3
• The infant has severe infection requiring hospitalization 2, 3