
Background: Vomiting is one of the postoperative complications of tonsillectomy. Aim of the study: This study was designed to determine the effectiveness of preoperative intravenous dexamethasone on postoperative emesis, starting oral intake and shorten the period of intravenous fluid. Methods: In a double – blind, placebo - controlled clinical trial,112 patients aged 5—12 years, ASA classes I were randomly selected to receive 2 mg / body weight (wt.) IV dexamethasone ( n = 56 ), as study group or an equivalent volume of saline preoperatively, as control group. The anesthetic regimen and surgical procedures were standardized for all patients. The incidence of early and late vomiting, the time to first oral intake and duration of intravenous hydration were compared in both groups. Results: Data analysis showed that the overall incidence of early and late vomiting was significantly lesser in dexamethasone group than the control one. The time to first oral intake and duration of IV therapy were also significantly shorter in dexamethasone group. Conclusion: A single dose of dexamethasone at induction of anesthesia significantly decreased the incidence of postoperative vomiting in early and late recovery phase and shortened the time to first oral intake and the duration of intravenous therapy.