We studied 24 patients undergoing elective cholecystectomy and randomized to either conventional postoperative pain treatment, with intermittent nicomorphine (10 to 15 mg) and acetaminophen (1 gm) on request, or thoracic epidural analgesia with plain bupivacaine for 48 hours and epidural morphine 4 mg every 8 hours for 96 hours plus systemic indomethacin 100 mg every 8 hours for 96 hours. Epidural analgesia for pin prick extended from the fourth thoracic to the first lumbar nerve for 48 hours. Assessments of pain, various injury response parameters, peak flow, and subjective feeling of fatigue were performed preoperatively, 3 and 6 hours after skin incision, and 1, 2, 4, and 8 days postoperatively. The epidural analgesia-systemic indomethacin treatment eliminated postoperative pain during rest and coughing. In contrast, only a minor and clinically unimportant modulation of the conventional perioperative and postoperative changes in plasma cortisol, glucose, transferrin, orosomucoid, leukocyte and differential counts, rectal temperature, peak flow, and fatigue was observed. Our results suggest that factors other than pain per se must be controlled in order to reduce postoperative morbidity.