title: Premedication with gabapentin, alprazolam or a placebo for abdominal hysterectomy: Effect on pre-operative anxiety, post-operative pain and morphine consumption.
abstract: OBJECTIVE
  Utility of gabapentin for pre-operative anxiolysis as compared to commonly administered alprazolam is not evident. The aim of the present study was to compare the effects of pre-operative oral gabapentin 600 mg, alprazolam 0.5 mg or a placebo on pre-operative anxiety along with post-operative pain and morphine consumption.
  
  
  METHODS
  Seventy five patients scheduled for abdominal hysterectomy under general anaesthesia were included. Groups gabapentin, alprazolam and placebo, received oral gabapentin 600 mg, alprazolam 0.5 mg and one capsule of oral B-complex forte with Vitamin C respectively, on the night prior to surgery and 2 h prior to surgery. Visual analogue scale (VAS) was used to measure the anxiety and post-operative pain. All patients received patient-controlled analgesia. Statistical tests used were Kruskal-Wallis test, Wilcoxon signed rank test and one-way ANOVA.
  
  
  RESULTS
  Alprazolam provided significant anxiolysis (median [interquartile range] baseline VAS score 35 [15.5, 52] to 20 [6.5, 34.5] after drug administration; P = 0.007). Gabapentin did not provide significant decrease in anxiety (median [interquartile range] VAS score 21 [7.5, 41] to 20 [6.5, 34.5]; P = 0.782). First analgesic request time (median [interquartile range in minutes]) was longer in group gabapentin (17.5 [10, 41.25]) compared to group placebo (10 [5, 15]) (P = 0.019) but comparable to that in group alprazolam (15 [10, 30]). Cumulative morphine consumption at different time periods and total morphine consumption (mean [standard deviation]) at the end of study period (38.65 [18.04], 39.91 [15.73], 44.29 [16.02] mg in group gabapentin, alprazolam and placebo respectively) were comparable.
  
  
  CONCLUSIONS
  Gabapentin 600 mg does not have significant anxiolytic effect compared to alprazolam 0.5 mg. Alprazolam 0.5 mg was found to be an effective anxiolytic in the pre-operative period. Neither alprazolam nor gabapentin, when compared to placebo showed any opioid sparing effects post-operatively.
authors.affiliation: Department of Anaesthesiology, Kasturba Medical College, Manipal University, Manipal, Karnataka, India.
authors.forename: Tim Thomas
authors.initials: TT
authors.lastname: Joseph
authors.affiliation: Department of Anaesthesiology, Kasturba Medical College, Manipal University, Manipal, Karnataka, India.
authors.forename: Handattu Mahabaleswara
authors.initials: HM
authors.lastname: Krishna
authors.affiliation: Department of Anaesthesiology, Kasturba Medical College, Manipal University, Manipal, Karnataka, India.
authors.forename: Shyamsunder
authors.initials: S
authors.lastname: Kamath
keywords: Alprazolam; anxiety; gabapentin; pain; post-operative prevention and control; psychological responses