Single and multiple dose cotrimoxazole and metronidazole in colorectal surgery.

Cotrimoxazole and metronidazole were given prophylactically to patients undergoing colorectal surgery as a single preoperative dose or in multiple doses for 5 days. A total of 60 operations randomly divided into two groups showed that the rate of wound infection was low in both groups and there was no statistical difference between them. There were no cases of anastomotic dehiscence in those patients where the anastomosis was carried out from within the abdomen, but 7 out of 9 patients with transphincteric colo-anastomoses developed a suture line dehiscence. A greater degree of post-catheterization urinary tract infection was seen in the single dose group (which lacks statistical significance). There were no toxic effects.