Objective: To compare the anti-emetic efficacy of metoclopramide alone and metoclopramide combined with dimenhydrinate. Materials & Methods: One hundred and fourteen female patients undergoing breast surgery were randomly allocated to receive either metoclopramide alone (metoclopramide group) or metoclopramide combined with dimenhydrinate (combination group) in a doubleblind manner. Metoclopramide in a dose of 0.15mg/kg (preformed in 10ml syringe) or similar dose of metoclopramide combined with 1mg/kg dimenhydrinate (preformed in 10ml syringe) was administered after induction of general anesthesia. Identical technique of general anesthesia was employed in all patients including intravenous induction with propofol, sevoflurane in N2O/O2 combination for maintenance and nalbuphine 0.15mg/ kg for analgesia Episodes of nausea & vomiting and the need for additional antiemetics were recorded post operatively for first 6 hours. Results: 78.94% patients in metoclopramide-group were free from postoperative nausea & vomiting, whereas in combination-group,100%patients were free from nausea and 98.24% patients were free from vomiting (P = 0.012). Conclusion: Combination of metoclopramide with dimenhydrinate is more effective than metoclopramide alone and therefore can be recommended for female patients undergoing breast surgery.