Purpose: To determine if preoperative pregabalin could decrease 24-h postoperative morphine consumption after spinal anesthesia with intrathecal morphine compared with placebo.

Methods: A randomized, double-blind, controlled trial was performed in the tertiary care center. Patients aged between 18 and 65 years who were American Society of Anesthesiologists class I-II and scheduled for abdominal hysterectomy with or without salpingo-oophorectomy were randomly allocated to a placebo or a pregabalin group. Patients received pregabalin 150 mg or placebo 1 h prior to anesthesia. Spinal anesthesia was achieved with 0.5% hyperbaric bupivacaine with morphine 0.2 mg. Intravenous patient-controlled analgesia morphine was provided postoperatively. Postoperative morphine consumption at 6, 12, and 24 h, time to first analgesic rescue, pain scores, adverse effects, and patient satisfaction were evaluated at 24 h after the operation.

Results: One hundred twenty-five patients were recruited and 119 patients (placebo N = 58, pregabalin N = 61) were included in the analysis. Forty-seven (81.0%) patients in the placebo group and 53 (86.9%) patients in the pregabalin group required morphine in the first 24 h. Median [IQR] 24-h morphine consumption was 4.0 [1.8, 10.0] mg in the placebo group and 5.0 [2.0, 11.0] mg in the prebagalin group, p = 0.60. There were no differences in cumulative morphine consumption at 6, 12, and 24 h postoperatively. The two groups also did not differ in time to first analgesic rescue, pain scores at rest and on movement, and side effects.

Conclusion: A single preoperative dose of pregabalin 150 mg did not reduce 24-h postoperative morphine consumption or pain scores or prolong the time to first analgesic rescue in spinal anesthesia with intrathecal morphine.