What is the recommended dosage of Cephalexin (Keflex) for surgical site infection?

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From the FDA Drug Label

The usual adult dose is 250 mg every 6 hours 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. For more severe infections or those caused by less susceptible organisms, larger doses may be needed If daily doses of cephalexin greater than 4 g are required, parenteral cephalosporins, in appropriate doses, should be considered.

The dosage for Keflex (cefalexin) for surgical site infection is not explicitly stated in the label. However, for skin and skin structure infections, the recommended dose is 500 mg every 12 hours or 250 mg every 6 hours.

  • For more severe infections, larger doses may be needed, but the label does not provide specific guidance for surgical site infections.
  • The maximum daily dose is 4 g, beyond which parenteral cephalosporins should be considered 1.

From the Research

For surgical site infections, the typical adult dosage of Keflex (cephalexin) is 500 mg taken orally every 6 hours, or 1 gram every 12 hours, for 7-14 days depending on infection severity, as supported by the most recent and highest quality study 2.

Key Considerations

  • The duration of treatment should be determined by your healthcare provider based on the specific infection characteristics, surgical site location, and your response to treatment.
  • Keflex works by inhibiting bacterial cell wall synthesis, making it effective against many common skin and soft tissue pathogens including Staphylococcus aureus (except MRSA) and Streptococcus species.
  • Take the full course of antibiotics even if symptoms improve before completion.
  • Common side effects include diarrhea, nausea, and rash.
  • If you have a penicillin allergy, inform your doctor as there is potential cross-reactivity.
  • Take Keflex with food if stomach upset occurs, and maintain adequate hydration during treatment.
  • Contact your healthcare provider if symptoms worsen or do not improve after a few days of treatment.

Additional Recommendations

  • Avoid razors for hair removal, as this can increase the risk of surgical site infections 2.
  • Maintain normothermia with active warming to keep the body temperature warmer than 36 °C 2.
  • Use chlorhexidine gluconate and alcohol-based skin preparation to reduce the risk of surgical site infections 2.
  • Consider decolonization with intranasal antistaphylococcal agents and antistaphylococcal skin antiseptics for high-risk procedures 2.
  • Control perioperative glucose concentrations to reduce the risk of surgical site infections 2.
  • Use negative pressure wound therapy to reduce the rate of surgical site infections 2.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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