Background & Objectives: Postoperative nausea and vomiting are among the main complication after anesthesia and various methods are used for the prevention of this complication. In this study, the effect of the pre induction use of 10mg Metoclopramide’ 8 mg Dexamethasone and the combination of the both, on decreasing in the rate of nausea and vomiting after cataract surgery in intravenous anesthesia is compared with placebo.

  Methods: In this double blind clinical trial, one hundred patients of cataract surgery who are appropriate for this study were, randomly divided in to four groups. In the group of placebo (P), 2cc normal saline, in group (M), 10mg metoclopramide, in group (D), 8mg Dexamethasone, and in group (M+D), 10mg metoclopramide and 8 mg Dexamethasone, one minute before the induction of anesthesia was injected. Patients were received the anesthetic drugs in the sameway and after the tracheal intubation infusion of propofol was started. After the end of surgical operation, the appearance of nausea and vomiting in the recovery room and also 6 and 24 hours after the surgery are recorded in the patients' information forms. Finally the data were analysed by statistical software of SPSS and the statistical tests.

  Results: After the use of these drugs, the rate of nausea in the recovery room decreased from 44% in placebo to 20% in metoclopromide group, 16% in Dexamethasone group, and 8% in combination of metoclopromide and Dexamethasone and the rate of vomiting decreased from 20% in placebo group to 4% in metoclopromide group, 4% in Dexamethasone group, and 0% in combination of these two drugs, both the nausea and vomiting the effect of combination of metoclopromide and Dexamethasone in decreasing of postoperative mausea and vomiting was significant (P<0.05). The 24 hour following of nausea and vomiting, also had the same results.

  Conclusion: With regrard to the results of this study, implication of the combination of 10mg metoclopromide and 8mg Dexamethasone before the induction of anesthesia remarkably decreased the rate of postoperative nausea and vomiting and is useful for the high risk groups for this complication especially in out patient surgery.