Different drugs have been used to enhance postoperative neuraxial opioid analgesia and reduce adverse effects of opioids .We studied whether administration of IV dexamethasone prior to intrathecalpethidinewith bupivacaine would enhance analgesia and minimize postoperative nausea and vomiting (PONV) compared with a control group.METHODS:The study was hospital based double blind placebo controlled randomized controlled trial conducted at S.M.S.Medical College and attached group of hospitals, Jaipur.We randomized 80 patients undergoing lower limb orthopaedic surgeries (duration 60-90 min) into 2 groups(40 each) to receive either 2 ml saline( group C) or 0.1 mg/kg dexamethasone IV( group D) before intrathecal anaesthesia(15 mg bupivacaine and pethidine 15 mg).After surgery, patients were asked to score their pain at 6, 12,18 and 24 hr by VAS score. IM Diclofenac 75 mg was given as rescue analgesic.The presence of PONV, pruritus and respiratory depression were recorded. PONV score and VAS score was compared between the groups using Mann-Whitney U test, variables measured on continuous scale by unpaired t-test and nominal data expressed as percentages by using Chi-square test.P value <0.05 was taken as significant.RESULTS:VAS pain scores at 6-hr intervals [p < 0.001],IM diclofenac requirements[P< 0.001] the incidence of PONV[p < 0.001 ] ,were significantly lower in the dexamethasone group than the control group (P < 0.05).CONCLUSIONS:We demonstrate that IV administration of dexamethasone (0.1 mg/kg) enhances the analgesic effect of intrathecalpethidineand reduces PONV.