On average the incidence of nausea or vomiting after general anesthesia ranges between 25 and 30% [Cohen 1994]. Nausea and vomiting can be extremely distressing for patients and is therefore one of their major concerns [Macario 1999]. Vomiting has been associated with major complications such as pulmonary aspiration of gastric content and might endanger surgical outcomes after certain procedures, for example after maxillofacial surgery with wired jaws. Nausea and vomiting can delay discharge and about 1% of patients scheduled for day surgery require unanticipated overnight admission because of uncontrolled postoperative nausea and vomiting.

Because no currently available antiemetic is especially effective by itself, and successful control is often elusive, experts recommend a multimodal approach. Anaesthetic strategies to prevent vomiting include using regional anaesthesia wherever possible and avoiding medications that cause vomiting. Medications to treat and prevent postoperative nausea and vomiting is limited by both cost and the adverse effects. People with risk factors probably warrant preventative medication, whereas a "wait and see" strategy is appropriate for those without risk factors.