What is the dosage and treatment protocol for Cefdinir (Cefdinir) for bacterial infections?

Cefdinir Dosage and Treatment Protocol for Bacterial Infections

Standard Dosing Regimens

Cefdinir is dosed at 300 mg twice daily or 600 mg once daily in adults and adolescents, and 14 mg/kg/day (maximum 600 mg/day) in one or two divided doses in pediatric patients aged 6 months and older, with treatment duration typically 5-10 days depending on the infection type. 1

Adult and Adolescent Dosing

• Community-acquired pneumonia: 300 mg twice daily for 10 days 1, 2
• Acute bacterial exacerbation of chronic bronchitis: 300 mg twice daily for 5-10 days 1, 3
• Acute maxillary sinusitis: 300 mg twice daily or 600 mg once daily for 10 days 1, 4
• Pharyngitis/tonsillitis: 300 mg twice daily for 5-10 days 1, 5
• Uncomplicated skin and skin structure infections: 300 mg twice daily for 10 days 1, 6

Pediatric Dosing (6 Months Through 12 Years)

The total daily dose is 14 mg/kg, up to a maximum of 600 mg per day, administered as either: 1

• 7 mg/kg every 12 hours (twice daily), OR
• 14 mg/kg every 24 hours (once daily)

Specific pediatric indications: 1

• Acute bacterial otitis media: 7 mg/kg q12h or 14 mg/kg q24h for 5-10 days (once-daily for 10 days)
• Acute maxillary sinusitis: 7 mg/kg q12h or 14 mg/kg q24h for 10 days
• Pharyngitis/tonsillitis: 7 mg/kg q12h or 14 mg/kg q24h for 5-10 days (once-daily for 10 days)
• Uncomplicated skin infections: 7 mg/kg q12h for 10 days (twice-daily dosing required; once-daily not studied for skin infections)

Special Populations

Renal Insufficiency

For patients with creatinine clearance <30 mL/min, reduce dose to 300 mg once daily in adults or 7 mg/kg once daily (up to 300 mg) in pediatric patients. 1

Hemodialysis Patients

• Initial dose: 300 mg (or 7 mg/kg) every other day 1
• Post-dialysis supplementation: 300 mg (or 7 mg/kg) at the conclusion of each hemodialysis session 1
• Maintenance: 300 mg (or 7 mg/kg) every other day between dialysis sessions 1

Clinical Efficacy and Spectrum

Antimicrobial Coverage

Cefdinir provides excellent activity against common community-acquired pathogens: 2, 3, 5

• Gram-positive organisms: Streptococcus pneumoniae (penicillin-susceptible strains with MIC <2.0 µg/mL), Staphylococcus aureus (methicillin-susceptible), Streptococcus pyogenes
• Gram-negative organisms: Haemophilus influenzae (including β-lactamase-producing strains), Moraxella catarrhalis (including β-lactamase-producing strains)
• Beta-lactamase stability: Stable to hydrolysis by 13 common beta-lactamases 3, 5

Important Coverage Limitations

Cefdinir is NOT recommended as first-line therapy for penicillin-resistant S. pneumoniae (MIC ≥4.0 µg/mL), methicillin-resistant S. aureus, or Pseudomonas aeruginosa. 7

For penicillin-resistant pneumococcal infections, preferred alternatives include high-dose amoxicillin (90 mg/kg/day), respiratory fluoroquinolones, or ceftriaxone. 7

Alternative Therapy When Cefdinir Fails

Treatment Failure Management

If no clinical response occurs after 72 hours of cefdinir therapy, switch to high-dose amoxicillin-clavulanate (90 mg/6.4 mg per kg per day in children or 4 g/250 mg per day in adults) or parenteral ceftriaxone (50 mg/kg/day in children or 1-2 g/day in adults). 8

For Cefdinir Allergy

In patients with cefdinir allergy, use clindamycin (30-40 mg/kg/day in 3 divided doses for children; 600-900 mg every 8 hours IV for adults) or sulfamethoxazole-trimethoprim as alternatives. 9

For respiratory infections with penicillin allergy in adults, respiratory fluoroquinolones (levofloxacin or moxifloxacin) are appropriate alternatives. 8

Administration Guidelines

Oral Suspension Preparation

• 125 mg/5 mL or 250 mg/5 mL concentrations: Add water in two portions, shake well after each addition 1
• Storage: Room temperature (25°C/77°F) in tightly closed container 1
• Stability: Use within 10 days after reconstitution; discard unused portion 1
• Administration: Shake well before each dose; may be given without regard to meals 1

Pharmacokinetic Considerations

• Time to peak concentration: Approximately 3 hours 3, 6
• Half-life: 1.5 hours 3, 6
• Tissue penetration: Good distribution into sinus tissue, tonsils, middle ear fluid, and skin blister fluid 2, 5
• Elimination: Almost entirely via renal clearance of unchanged drug 3, 6

Common Pitfalls and Caveats

Diarrhea is the most common adverse event, occurring in approximately 20% of patients, which may be higher than some comparator agents but rarely requires discontinuation. 5, 4

Once-daily dosing has NOT been studied for skin infections; therefore, twice-daily administration is required for uncomplicated skin and skin structure infections. 1

Cefdinir should not be used as monotherapy for severe pneumonia requiring ICU admission or for infections where MRSA or Pseudomonas aeruginosa are suspected. 7

In areas with high rates of penicillin-resistant S. pneumoniae or MRSA, consider alternative agents or combination therapy based on local resistance patterns. 7, 9