From the Guidelines
Cefalex (Cephalexin) should be prescribed at a dose of 500 mg orally four times daily for adults with uncomplicated cellulitis, as recommended by the practice guidelines for the diagnosis and management of skin and soft-tissue infections 1.
Key Considerations
- The usual treatment duration is 5-10 days, depending on the severity of the infection and clinical response.
- For children, the recommended dose is 25 mg/kg/day divided into four equal doses, as outlined in the guidelines 1.
- It is essential to complete the full course of antibiotics even if symptoms improve before finishing the medication.
Mechanism of Action and Efficacy
- Cephalexin works by inhibiting bacterial cell wall synthesis, making it effective against many of the common skin pathogens that cause cellulitis, particularly Streptococcus and Staphylococcus species.
- Patients should take the medication with food if stomach upset occurs, stay well-hydrated, and contact their healthcare provider if symptoms worsen, if fever persists beyond 48-72 hours of treatment, or if a rash develops.
Important Precautions
- Those with penicillin allergies should inform their doctor as there is potential for cross-reactivity with cephalosporins.
- The guidelines also recommend considering alternative treatments, such as clindamycin or doxycycline, for patients with methicillin-resistant Staphylococcus aureus (MRSA) infections 1.
From the FDA Drug Label
For the following infections, a dosage of 500 mg may be administered every 12 hours: streptococcal pharyngitis, skin and skin structure infections, and uncomplicated cystitis in patients over 15 years of age. The recommended dose of cefalexin for cellulitis, which is a type of skin and skin structure infection, is 500 mg every 12 hours 2.
- The dose may be adjusted based on the severity of the infection.
- For more severe infections, larger doses may be needed.
From the Research
Ceflex Dose for Cellulitis
- The studies provided do not specifically mention the dose of cephalexin (also known as ceflex) for cellulitis, but they do discuss the effectiveness of cephalexin with or without trimethoprim-sulfamethoxazole for treating uncomplicated cellulitis 3, 4.
- In the study by Pallin et al. (3), patients received cephalexin, and the outcome was compared with those who received cephalexin plus trimethoprim-sulfamethoxazole.
- Another study (4) compared the effectiveness of cephalexin plus trimethoprim-sulfamethoxazole with cephalexin alone for treating uncomplicated cellulitis, but the dose of cephalexin was not specified.
- A study by Chen et al. (5) compared treatment success rates for empiric therapy with cephalexin, trimethoprim-sulfamethoxazole, and clindamycin, but the dose of cephalexin was not mentioned.
- The study by Stevens et al. (6) evaluated the cost-effectiveness of using cephalexin, trimethoprim/sulfamethoxazole, or clindamycin for outpatient empiric therapy of cellulitis, but the dose of cephalexin was not specified.
Treatment Outcomes
- The studies suggest that cephalexin is effective for treating uncomplicated cellulitis, but the addition of trimethoprim-sulfamethoxazole does not improve outcomes overall or by subgroup 3, 4.
- The study by Chen et al. (5) found that trimethoprim-sulfamethoxazole had a higher treatment success rate than cephalexin, but this may be due to the high prevalence of community-associated MRSA in the study population.
- The study by Stevens et al. (6) found that cephalexin was the most cost-effective option for outpatient empiric therapy of cellulitis, but clindamycin became more cost-effective at high likelihoods of MRSA infection.
Antibiotic Choice
- The choice of antibiotic for treating cellulitis depends on the suspected causative organism and the presence of purulent drainage or abscess 7.
- For uncomplicated cellulitis without purulent drainage or abscess, cephalexin may be a suitable choice, but the dose and duration of treatment should be determined based on clinical guidelines and patient-specific factors 3, 4.