BACKGROUND: This study was undertaken to evaluate the analgesic effect of a self administered surgical wound infusion of local anesthetic alone compared to combination of local anesthetic and morphine or ketorolac. METHOD: Forty eight patients undergoing minor surgery were randomly classified into four groups: Group 1 (saline, n = 10), Group 2 (bupivacaine only, n = 11), Group 3 (bupivacaine with morphine, n = 14), and Group 4 (bupivacaine with ketorolac, n = 13). A two-hole 19 G epidural catheter was tunneled subcutaneously into the surgical wound and was connected to 100 ml elastometric balloon pump filled with either 0.5% bupivacaine only, 0.5% bupivacaine and morphine 40 mg, or 0.5% bupivacaine and ketorolac 80 mg. We assessed the postoperative visual analogue scale (VAS) pain scores at postoperative 0.5, 1, 2, 6, 12, 24, 36, and 48 hours, and the side effects, sedation score and total amount of infused bupivacaine were recorded. RESULTS: VAS pain score were significantly decreased until 36 hours in groups 2, 3, and 4 compared to group 1, and significantly lower at 1, 2, 12, and 24 hrs in groups 3, 4 than in group 2 (P < 0.05). The total requirement of infused bupivacaine in groups 3, 4 is significantly decreased compared to that of group 2. Side effects like nausea, vomiting, urinary retension, pruiritis, respiratory difficulty, sedation, and dizziness did not occur in the four groups but seroma did in one case. CONCLUSION: Patient-controlled surgical wound infusion of bupivacaine reduced postoperative pain after minor surgery without any side effects. The combination of bupivacaine with morphine or ketorolac gave rise to a significant additive effect to local analgesia.