Background: To date, there are no controlled studies assessing the effect of metoclopramide administered epidurally to prevent nausea and vomiting associated with epidural morphine for postoperative analgesia. This study was undertaken to determine the effectiveness of continuous epidural infusion of metoclopramide, combined with epidural morphine, in reducing nausea or vomiting associated with epidural morphine and minimizing the side effects of metoclopramide. Methods: Sixty patients undergoing elective gynecologic surgery were randomly assigned to one of two study groups. Patients received continuous epidural morphine infusion (6.0 mg/day) following a bolus loading dose of 3.0 mg (Group A), or epidural mixture of morphine (6.0 mg/day) plus metoclopramide (20 mg/day) following a bolus loading dose (morphine 3.0 mg, metoclopramide 10 mg)(Group B). For the first 24 postoperative hours, incidence of nausea or vomiting, need for antiemetic therapy, level of sedation, degree of pain and pruritus, and adverse effects associated with metoclopramide were evaluated. Result: Incidence of nausea or vomiting and number of patients who required antiemetic therapy were significantly less in Group B, than in Group A (P<0.05). There were no significant differences between groups with regard to adverse effects associated with metoclopramide such as sedation, extrapyramidal reaction and other side effects (P=NS). Conclusion: We conclude simultaneous titration of morphine and metoclopramide via epidural continuous infusion following epidural bolus injection of the mixture reduces nausea or vomiting associated with epidural morphine while preventing side effects of metoclopramide.