The effect of opioids on the development of postoperative intra-abdominal adhesions.

People addicted to opium rarely develop intra-abdominal adhesions after abdominal surgery. We aimed to evaluate the effect of opium or morphine on preventing postoperative adhesions in rats. Sixty-three rats were randomly divided into a control group, opium-addicted group, and morphine-addicted group in a double-blind study. Drug dependency was checked by using naloxone. Animals were then operated on and the cecum was abraded. At reoperation 3 weeks later the magnitude of adhesions was evaluated by a scoring system. There was a significant difference between the control, opium-addicted, and morphine-addicted groups with regard to the length (P < .001), thickness (P < .05), and severity of adhesions (P < .05). Opium or morphine reduces the severity of postoperative adhesions. Elucidation of the opioid receptor(s) involved in this process would enable the use of selective ligands and offer a pharmacologic strategy in preventing adhesion formation.