Background and objectives: To evaluate the effectiveness of acupressure in preventing nausea and vomiting in patients undergoing gynaecological operations and receiving a patient-controlled analgesia device. Methods: Patients aged between 40 and 65 yr were included. Exclusion criteria were obesity, diabetes mellitus, and history of motion sickness, postoperative nausea and vomiting, or smoking. Patients were randomized into one of two groups, acupressure and control. In the acupressure group, acupressure bands were placed on both wrists with the plastic bead positioned at the P6 point. In controls, beads were placed at a non-acupoint site. All patients received a standard general anaesthetic. Postoperatively, patients were connected to a patient-controlled analgesia device with morphine (loading dose 5 mg, background infusion 1 mg h−1, bolus dose 1 mg and lock-out time 10 min). Pain and sedation scores, respiratory rate, heart rate, arterial pressure and oxygen saturation were recorded for 24 h. Metoclopramide 10 mg was administered intravenously as a rescue antiemetic. Results: Fifty patients received acupressure and 50 were controls. In the acupressure group, 33% of patients had nausea compared with 63% controls. The cumulative incidence of vomiting at 24 h was 25% with acupressure and 61% in controls. The incidence of nausea, vomiting and antiemetic use was significantly lower with acupressure. Conclusions: Acupressure at the P6 meridian point is an effective alternative for the prevention of nausea and vomiting in patients receiving patient-controlled analgesia with morphine after gynaecological surgery.