SummaryDespite common clinical opinion that patient-controlled analgesia should be renamed 'patientcontrolled nausea', there is little evidence in support of the notion that postoperative nausea and vomiting are exacerbated by the method. Indeed, data indicate that opioid-sparing techniques are not associated with less postoperative nausea and vomiting. Although some evidence suggests that certain opioids are less emetogenic than others, this too does not stand scrutiny when compared across patients, although research is still required to find whether individual patients are better treated with a particular opioid. Similarly, the emerging practice of combining anti-emetics with patient-controlled analgesia needs wider study before it can be supported. Nausea and vomiting are distressing adverse events which frequently follow surgery. The incidence of postoperative nausea and vomiting is difficult to estimate because of methodological differences between studies; however, there are reports of from 8% to 92% of postsurgical patients experiencing postoperative emesis [1]. Lerman [2] and Watcha & White [3] suggest that the incidence of postoperative nausea and vomiting has remained fairly constant for decades with Ϸ20-30% of patients suffering from these unpleasant side-effects. However, it is common to find reports of a much higher incidence in a variety of surgical populations [4][5][6][7][8][9][10]. Differentiation of opioidinduced nausea and vomiting from that of other perioperative factors, including those associated with uncontrolled pain [11], is difficult enough without complications introduced by patient-controlled analgesia (PCA) which allows patients to medicate on irregular and inconsistent bases. This review focuses on the issues associated with nausea and vomiting as encountered in the postoperative PCA environment.