Effect of a single dose of pregabalin on post-operative pain and pre-operative anxiety in patients undergoing discectomy

Background Pregabalin acts as a membrane stabilizer and has both analgesic and anxiolytic effects. We hypothesized that one pre-operative dose of pregabalin would reduce pre-operative anxiety and post-operative pain in patients undergoing discectomy. Methods We performed a randomized, placebo-controlled study of 150 mg pregabalin administered before lumbar discectomy in general anaesthesia. The primary endpoint was pain at rest [visual analogue scale (VAS)] 120 min after surgery. The secondary outcomes were morphine consumption, pre-operative anxiety (VAS) and the occurrence of side effects. Results The VAS scores for pain at rest and morphine consumption were higher in the placebo group during the 4-h stay in the post-anaesthetic care unit (PACU), but did not differ significantly 24 h after surgery. Pain scores at 7 days were similar and there was no difference in the occurrence of side effects. Pre-operative anxiety was significantly lower in the pregabalin group (2.23 +/- 1.11 vs. 4.17 +/- 2.37, 95% confidence interval: 0.82-3.05, P=0.001) and there was a significant positive correlation between the pre-operative anxiety score and post-operative pain at 120 min in the pregabalin group. Conclusions A single dose of pregabalin (150 mg) reduced post-operative pain at rest and morphine consumption during the PACU period after lumbar discectomy. Pre-operative anxiety was lower, without increased incidence of side effects.