Clinical Practice Guidelines for Antimicrobial Prophylaxis in Surgery provide a standardized approach to the rational, safe, and effective use of antimicrobial agents for preventing surgical site infections (SSIs). Developed by ASHP, IDSA, SIS, and SHEA, these guidelines update previous recommendations and consider current clinical evidence and emerging issues. Prophylaxis is categorized into primary, secondary, and eradication, with a focus on primary perioperative prophylaxis. The guidelines emphasize the importance of timing, selection, and duration of antimicrobial use. Preoperative doses should be administered within 60 minutes before surgical incision, with some agents requiring administration up to 120 minutes. Dosing is based on body weight, especially in obese patients, and may require repeat doses during prolonged procedures. The guidelines also address the use of specific antimicrobial agents for different procedures, including alternatives for patients with allergies to β-lactam antimicrobials. The guidelines recommend a single preoperative dose for most procedures, with a duration of less than 24 hours postoperatively. They also address special populations, such as pediatric patients and those with prosthetic implants, noting that antimicrobial prophylaxis may not be necessary for all cases. The guidelines emphasize the importance of considering local resistance patterns and institutional factors when selecting antimicrobial agents. The guidelines also discuss the cost-effectiveness of antimicrobial prophylaxis, the importance of proper drug administration and timing, and the need for quality improvement efforts to ensure appropriate use. They highlight the role of antimicrobial agents in reducing SSI rates, while acknowledging that other factors, such as infection control practices and patient characteristics, also influence SSI rates. The guidelines provide recommendations for the use of specific antimicrobial agents, including cefazolin as the drug of choice for most procedures. They also address the use of vancomycin for patients with known MRSA colonization or at high risk for MRSA colonization. The guidelines emphasize the importance of individualized care, considering patient-specific factors and available resources when making decisions about antimicrobial prophylaxis.Clinical Practice Guidelines for Antimicrobial Prophylaxis in Surgery provide a standardized approach to the rational, safe, and effective use of antimicrobial agents for preventing surgical site infections (SSIs). Developed by ASHP, IDSA, SIS, and SHEA, these guidelines update previous recommendations and consider current clinical evidence and emerging issues. Prophylaxis is categorized into primary, secondary, and eradication, with a focus on primary perioperative prophylaxis. The guidelines emphasize the importance of timing, selection, and duration of antimicrobial use. Preoperative doses should be administered within 60 minutes before surgical incision, with some agents requiring administration up to 120 minutes. Dosing is based on body weight, especially in obese patients, and may require repeat doses during prolonged procedures. The guidelines also address the use of specific antimicrobial agents for different procedures, including alternatives for patients with allergies to β-lactam antimicrobials. The guidelines recommend a single preoperative dose for most procedures, with a duration of less than 24 hours postoperatively. They also address special populations, such as pediatric patients and those with prosthetic implants, noting that antimicrobial prophylaxis may not be necessary for all cases. The guidelines emphasize the importance of considering local resistance patterns and institutional factors when selecting antimicrobial agents. The guidelines also discuss the cost-effectiveness of antimicrobial prophylaxis, the importance of proper drug administration and timing, and the need for quality improvement efforts to ensure appropriate use. They highlight the role of antimicrobial agents in reducing SSI rates, while acknowledging that other factors, such as infection control practices and patient characteristics, also influence SSI rates. The guidelines provide recommendations for the use of specific antimicrobial agents, including cefazolin as the drug of choice for most procedures. They also address the use of vancomycin for patients with known MRSA colonization or at high risk for MRSA colonization. The guidelines emphasize the importance of individualized care, considering patient-specific factors and available resources when making decisions about antimicrobial prophylaxis.