Background: This study was conducted to evaluate the efficacy of a parenteral nonsteroidal anti-inflammatory agent for management of post-surgical pain and its effect on hospital stay and long-term surgical outcome. Methods: Total of 40 patients undergoing lumbar discectomy were randomly assigned to two groups, receiving either 1) 30 mg intravenous ketorolac upon surgical closure, every 6 hours for 36 hours, and morphine IV PCA (intravenous patient controlled analgesia), or 2) only morphine PCA. A blinded investigator recorded; the visual analog pain scores, total postoperative narcotic consumption, complications by morphine PCA, length of hospitalization (from surgery to discharge), and long-term outcome at 6 weeks. Results: The patients who received IV ketorolac and morphine PCA reported significantly lower visual analog pain scores than patients receiving only morphine PCA. Cumulative morphine doses were significantly lower in the ketorolac group (P<0.001). There was no significant difference between groups in the frequency of side effects related to morphine PCA. Mean length of hospitalization was longer for patients receiving only morphine PCA, but there was no statistical significance. Six weeks after surgery, four (20.0%) patients who received only morphine PCA suffered persistent back pain. In contrary, all those patients who received ketorolac were free of back pain at follow-up (P<0.05). Conclusions: These results suggest that intermittent IV bolus ketorolac, when used with opioid IV PCA is more effective than opioid IV PCA alone for postoperative pain following lumbar disc surgery. However, this strategy did not contribute to early discharge from hospital after lumbar disc surgery. The effect to long-term surgical outcome was not conclusive.