Background: Selective inhibitors of inducible cyclo-oxygenase (COX-2) are of potential benefit in the perioperative period for both their analgesic and, perhaps, antineoplastic actions. However, their effects on laparotomy and intestinal wound healing are unknown.Methods: Forty adult Sprague-Dawley rats underwent laparotomy, descending colonic transection and handsewn reanastomosis. The animals were randomized to receive either a selective COX-2 inhibitor (rofecoxib, 10 mg/kg) or an equal volume of water by gavage before operation and then daily after surgery. Animals were killed after 3 or 7 days, and their wounds were evaluated by means of tensiometry (skin and colonic wounds) and bursting pressure measurement (colonic anastomoses). In addition, haematoxylin and eosin-stained intestinal sections were examined and scored by a blinded independent observer.Results: Five animals that received rofecoxib had anastomotic leaks by day 7 compared with none in the control group (P = 0.048). Intact colonic suture lines were also significantly weaker in this group (tensile strength at day 3, P = 0.043; bursting pressure on days 3 and 7, both P = 0.019). Skin wound strengths were similar in the two groups at both time points.Conclusion: Although beneficial in the treatment of pathological inflammation, selective COX-2 inhibitors may adversely affect colonic anastomotic healing.