Antibiotics covering aerobic and aerobic bacteria should be delivered orally and intravenously prior to colorectal surgery.  Antibiotics delivered within this framework will reduce the risk of postoperative SWI by at least 75%.  Further research is required to establish the optimal timing and duration of dosing, and frequency of longer-term adverse effects such as Clostridium difficile pseudomembranous colitis.
Single versus multiple dose doxycycline prophylaxis in elective colorectal surgery.
One hundred and two patients undergoing elective colorectal surgery were randomized in a prospective but "non-blind" way into two groups. The first group received 0.4 g of doxycycline preoperatively and the second group 0.2 g of doxycycline preoperatively and 0.1 g of doxycycline on the first, second and third postoperative day. All doxycycline was administered by intravenous infusion. The infection rate was 10% in the "one-dose" treatment group and 10% in the "four-dose" treatment group. It is thus concluded that 0.4 g of doxycycline preoperatively results in an acceptable rate of postoperative infections, which may be explained by the satisfactory concentration of doxycycline up till three days after administration. The advantage of "one-dose" treatment compared to "four-dose" treatment from practical and economical standpoints are obvious.