This is a large prospective study of the effect of intravenous acetaminophen (paracetamol) in orbital surgery. The study included three groups of 50 patients. One group had no i.v. paracetamol, the second 1g of i.v. paracetamol within 30 minutes of the start of surgery, and the third group 1g i.v. paracetamol immediately preoperatively. The authors assessed pain scores, analgesic and antiemetic requirements postoperatively. They found a significant difference in the pain scores in favour of the paracetamol groups compared with the control. Likewise there were also statistically significant differences in the requirement for analgesics postoperatively, in favour of the paracetamol groups. If the paracetamol was given immediately prior to the start of surgery there was also a significant reduction in the requirement for antiemetics. Although i.v. paracetamol use has been reported in other surgery, this is the first report in orbital surgery, and this large study provides strong evidence for its efficacy. The main weakness of the trial was the lack of randomisation, and given that orbital surgery encompasses a wide range of procedures, there is potential for bias. However, the large numbers should compensate for this.