The effect of the diclofenac sodium (DS) on the healing of anastomosis carried- out in the ileum of rats was studied. Five- hundred and nineteen Wistar rats were randomly assigned to the 4 experimental groups: Group I included 52 rats treated with 3 mg/kg/day of saline, administered intramusculary during 4 days, group II included 110 rats submitted to ileal anastomosis and treated with saline as described previously, group III included 52 rats treated with DS in a dose of 3 mg/kg/day, administered IM during 4 days, and group IV included 295 rats submitted to ileal anastomosis and treated with DS as prior described. In all rats from the 4 experimental groups clinical parameters and measurements of tensile strength, tissue collagen and histological analyses were documented at 4, 7, 14, and 21 postoperative days. There are no clinical alterations in group I rats all over the study. Diarrhoea was observed in 8 rats (15,4%) from group III. In this group both tensile strenght and tissue collagen were descrease when compared with group I rats. Mortality in DS treated rats submitted to ileal anastomosis was higher than those of control groups. In group IV we also observed reard in the healing, with intense PMN inflamatory response, decrease of macrophages and of tissue collagen, and mucosae regeneration. We concluded that DS is deleterious on the healing of anastomosis performed in the ileum of rats
