What is the recommended dosage of Cephalexin (Cefalexin) for pediatric patients with cellulitis?

From the Guidelines

For pediatric cellulitis, cephalexin is typically dosed at 25-50 mg/kg/day divided into four equal doses (given every 6 hours), with a maximum of 4 grams per day, as recommended by the Infectious Diseases Society of America guidelines 1.

Key Considerations

• The dosage of cephalexin for pediatric cellulitis is based on the child's weight, with a recommended dose of 25-50 mg/kg/day divided into four equal doses.
• The treatment duration is usually 7-10 days, but may be extended based on clinical response.
• Cephalexin is available in various formulations, including capsules, tablets, and oral suspension, with the suspension formulation preferred for young children.
• It is essential to monitor for clinical improvement within 48-72 hours, including decreased erythema, swelling, and pain.
• Cephalexin is effective against most Staphylococcus aureus (except MRSA) and Streptococcus species, which are common causes of cellulitis.

Important Notes

• If MRSA is suspected or the infection is severe, alternative antibiotics may be necessary, as cephalexin is not effective against MRSA.
• Ensure adequate hydration during treatment and complete the full course of antibiotics even if symptoms improve quickly to prevent recurrence or resistance development.
• The guidelines also recommend considering the presence or absence of systemic inflammatory response syndrome (SIRS) when deciding on antibiotic treatment, as patients with SIRS may require more aggressive treatment 2.

Formulations and Administration

• Cephalexin is available as capsules (250 mg, 500 mg), tablets (250 mg, 500 mg), and oral suspension (125 mg/5 mL, 250 mg/5 mL).
• For young children, the suspension formulation is preferred due to its ease of administration and flexibility in dosing.
• The oral suspension should be shaken well before administration to ensure accurate dosing.

From the FDA Drug Label

Pediatric Patients The usual recommended daily dosage for pediatric patients is 25 to 50 mg/kg in divided doses For streptococcal pharyngitis in patients over 1 year of age and for skin and skin structure infections, the total daily dose may be divided and administered every 12 hours. In severe infections, the dosage may be doubled.

The recommended pediatric dosing for cellulitis (a type of skin and skin structure infection) is 25 to 50 mg/kg in divided doses, which can be administered every 12 hours. In severe infections, the dosage may be doubled 3.

• The dosage can be calculated based on the child's weight, with the following examples: + 10 kg (22 lb): 1 to 2 tsp b.i.d. (for 125 mg/5 mL suspension) or 1/2 to 1 tsp b.i.d. (for 250 mg/5 mL suspension) + 20 kg (44 lb): 2 to 4 tsp b.i.d. (for 125 mg/5 mL suspension) or 1 to 2 tsp b.i.d. (for 250 mg/5 mL suspension) + 40 kg (88 lb): 4 to 8 tsp b.i.d. (for 125 mg/5 mL suspension) or 2 to 4 tsp b.i.d. (for 250 mg/5 mL suspension)

From the Research

Cephalexin Pediatric Dosing in Cellulitis

• The effectiveness of high-dose oral cephalexin for treating moderate cellulitis in children has been evaluated in a retrospective cohort study 4.
• The study found that high-dose oral cephalexin was effective and safe for treating children with moderate cellulitis, with a success rate of 89.7% 4.
• The use of cephalexin for treating cellulitis is also supported by a review of current practice guidelines, which recommends oral antibiotics such as penicillin, amoxicillin, and cephalexin for non-purulent, uncomplicated cases of cellulitis 5.
• A descriptive case-control study found that cephalexin was the most commonly prescribed oral antibiotic for treating noncomplicated, nonfacial cellulitis in children, with a treatment failure rate of 8.9% 6.
• The choice of antibiotic and dosage should be guided by pharmacodynamic principles and antimicrobial stewardship programs to optimize treatment outcomes 7.
• While cephalexin is a commonly used antibiotic for treating cellulitis, other antibiotics such as amoxicillin-clavulanate may be associated with shorter hospital stays and fewer treatment failures 8.

Key Findings

• High-dose oral cephalexin is effective and safe for treating moderate cellulitis in children 4.
• Cephalexin is a commonly prescribed oral antibiotic for treating noncomplicated, nonfacial cellulitis in children 6.
• The choice of antibiotic and dosage should be guided by pharmacodynamic principles and antimicrobial stewardship programs 7.

Antibiotic Treatment Options

• Cephalexin is a recommended oral antibiotic for treating non-purulent, uncomplicated cases of cellulitis 5.
• Amoxicillin-clavulanate may be associated with shorter hospital stays and fewer treatment failures 8.
• Other antibiotics such as penicillin, amoxicillin, and cefuroxime may also be used to treat cellulitis 5, 7.