Pregabalin has anticonvulsant, antihyperalgesic, and anxiolytic properties. In this study we evaluated the control of pain after perioperative administration of pregabalin 300 or 600 mg, compared with diazepam 10mg. Altogether 91 women scheduled for laparoscopic hysterectomy were randomized to receive diazepam 10mg (D10), pregabalin 150 mg (P300) or 300 mg (P600) for premedication, and the dose was repeated after 12h, except for the D10 group, in which the patients received placebo. Up until the 1st postoperative morning, analgesia was provided by oxycodone using patient controlled analgesia. The visual analogue scale scores for pain and side effects, and the amounts of the analgesics were recorded for three days after surgery. The doses of oxycodone during hours 0-12 after surgery were similar in the three groups, whereas the dose of oxycodone during hours 12-24 after surgery was smaller in the P600 group than in the P300 group (0.09 vs. 0.16 mg kg(-1); P=0.025). The total dose of oxycodone (0-24h after surgery) was smaller in the P600 group than in the D10 group (0.34 vs. 0.45 mg kg(-1); P=0.046). The incidence of dizziness (70% vs. 35%; P=0.012), blurred vision (63% vs. 14%; P=0.002) and headache (31% vs. 7%; P=0.041) were higher in the P600 group than in the D10 group. In conclusion, perioperative administration of pregabalin 600 mg decreases oxycodone consumption compared with diazepam 10mg, but is associated with an increased incidence of adverse effects.