What is the recommended cefdinir dosage for adults and children, and how should it be adjusted in renal impairment?

Cefdinir Dosage

For adults and adolescents, cefdinir is dosed at 300 mg twice daily or 600 mg once daily; for children 6 months through 12 years, the dose is 7 mg/kg every 12 hours or 14 mg/kg once daily (maximum 600 mg/day), with dose reduction to 300 mg once daily (or 7 mg/kg once daily) for patients with creatinine clearance <30 mL/min. 1

Adult and Adolescent Dosing

• Standard dose: 300 mg orally twice daily OR 600 mg orally once daily 1, 2
• Treatment duration: 5-10 days depending on the infection type 1, 3
• The drug may be administered without regard to meals, though taking with meals may improve gastrointestinal tolerability 1

Pediatric Dosing (Age 6 Months Through 12 Years)

• Total daily dose: 14 mg/kg/day, up to a maximum of 600 mg per day 1
• Dosing options: 7 mg/kg every 12 hours OR 14 mg/kg once daily 1, 4
• Important caveat: Once-daily dosing has not been studied for skin infections, so twice-daily administration (7 mg/kg every 12 hours) should be used for uncomplicated skin and skin structure infections 1

Specific Pediatric Indications and Duration

• Acute bacterial otitis media: 5-10 days (twice daily) or 10 days (once daily) 1
• Acute maxillary sinusitis: 10 days 1
• Pharyngitis/tonsillitis: 5-10 days (twice daily) or 10 days (once daily) 1
• Uncomplicated skin infections: 10 days (twice daily only) 1

Weight-Based Pediatric Dosing Chart

• 9 kg (20 lbs): 2.5 mL every 12h or 5 mL every 24h (using 125 mg/5 mL suspension) 1
• 18 kg (40 lbs): 5 mL every 12h or 10 mL every 24h (125 mg/5 mL) OR 2.5 mL every 12h or 5 mL every 24h (250 mg/5 mL) 1
• 27 kg (60 lbs): 7.5 mL every 12h or 15 mL every 24h (125 mg/5 mL) OR 3.75 mL every 12h or 7.5 mL every 24h (250 mg/5 mL) 1
• 36 kg (80 lbs): 10 mL every 12h or 20 mL every 24h (125 mg/5 mL) OR 5 mL every 12h or 10 mL every 24h (250 mg/5 mL) 1
• ≥43 kg (95 lbs): Maximum dose of 600 mg/day: 12 mL every 12h or 24 mL every 24h (125 mg/5 mL) OR 6 mL every 12h or 12 mL every 24h (250 mg/5 mL) 1

Renal Impairment Dosing

Adults with Renal Insufficiency

• Creatinine clearance <30 mL/min: Reduce dose to 300 mg once daily 1
• Hemodialysis patients: 300 mg (or 7 mg/kg) every other day; give 300 mg (or 7 mg/kg) at the conclusion of each hemodialysis session, then continue every other day dosing 1

Pediatric Patients with Renal Insufficiency

• Creatinine clearance <30 mL/min/1.73 m²: 7 mg/kg (up to 300 mg) once daily 1
• Hemodialysis patients: 7 mg/kg every other day; give 7 mg/kg at the conclusion of each hemodialysis session, then continue every other day dosing 1

Estimating Creatinine Clearance

For adults (when serum creatinine reflects steady-state renal function): 1

• Males: CLcr = (weight in kg) × (140 - age in years) / [(72) × (serum creatinine in mg/dL)]
• Females: CLcr = 0.85 × above value

For pediatric patients: 1

• CLcr = K × (body length or height in cm) / (serum creatinine in mg/dL)
• K = 0.55 for children >1 year
• K = 0.45 for infants (up to 1 year)

Clinical Context and Spectrum of Activity

• Cefdinir has broad-spectrum activity against common respiratory and skin pathogens including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Streptococcus pyogenes 2, 4
• The drug is stable against 13 common beta-lactamases, making it effective against beta-lactamase-producing strains of H. influenzae and M. catarrhalis 4, 3
• Cefdinir is listed as an alternative oral agent for Haemophilus influenzae infections in pediatric community-acquired pneumonia when beta-lactamase production is present 5

Common Pitfalls and Adverse Effects

• Diarrhea is the most common adverse event, occurring in approximately 20% of patients, though this is generally mild 3, 6
• In some studies, diarrhea occurred significantly more frequently with cefdinir than with comparators like penicillin V, cephalexin, cefaclor, and cefprozil 4
• Despite higher diarrhea rates, discontinuation rates due to adverse events are generally similar to comparator agents 3, 6
• The oral suspension has demonstrated superior taste and palatability compared to other oral antimicrobial agents, improving pediatric compliance 2, 3