<prompt> When do we have to sta antibiotics to prevent post-operative infection?2 days before surgeryAfter surgery1 week before surgery1 hour before surgery continue after surgery  <response>: Ans. is d i.e., 1 hour before surgery continue after surgery Prophylactic antibiotics are administered before the skin incision is made. Repeat dosing occurs at an appropriate interval, usually 3 hours for abdominal cases or twice the half-life of the antibiotic. Perioperative antibiotic prophylaxis generally is not continued beyond the day of surgery. 