A systematic review including 21 studies was abstracted in DARE. The results of the meta-analysis for droperidol indicated an OR of 0.27 (95% CI: 0.21 to 0.34), with a highly significant decrease in nausea and vomiting when compared with the placebo group. The OR was 0.48 (95% CI: 0.30 to 0.75) for metoclopramide, and 0.23 (95% CI: 0.15 to 0.35) for dexamethasone. The results for propofol indicated an OR of 1.09 (95% CI: 0.61 to 1.95, p <0.8) with no significant increase in the incidence of nausea and vomiting. The results for ondansetron indicated an OR of 0.40 (95% CI: 0.13 to 1.22), with a decreased tendency for nausea and vomiting.
Comment: The quality of evidence is downgraded by review quality (serius flaws in the data analysis).