Pregabalin Ameliorated Abdominal Pain from Adhesions

Abstract

Purpose: Abdominal pain is a common post-surgical complication that lacks effective therapy. Pregabalin is FDA approved for treatment of neuropathic pain. The purpose of this study was to determine if pregabalin ameliorates abdominal pain from adhesions. Methods: We designed a double-blind placebo-controlled 12-week crossover study using pregabalin to treat patients with abdominal pain from adhesions defined as a negative evaluation for abdominal pain and documented adhesions within 5 years. The first 8 weeks was a randomized placebo controlled trial of pregabalin followed by a 4 week open label study for all patients. Our primary objectives were to demonstrate a significant reduction in pain scores on the 11 point Likert scale and a 2 point pain score drop from baseline. A secondary objective analyzed was improvement in sleep score based on an 11 point Likert scale. Results: Eighteen women enrolled in the study, mean age, 46.05. Eleven patients received drug and 9 placebo. The study was discontinued early because of low enrollment. Seven patients withdrew from the study early (4 placebo, 3 drug). One patient on study drug was withdrawn after hospital admission for suicidal ideation. Using intention to treat analysis, the pain score drop was significantly greater in the pregabalin group than in the placebo group (p=0.024) during the randomized treatment. In addition the pregabalin group but not the control group (-3.62 vs -1.88) had a mean decrease in pain score of greater than 2. The sleep score improvement was greater in pregabalin patients but this difference was not significant (p=0.375). The sleep score improvements dropped more than 2 points in the pregabalin but not placebo patients (-2.34 vs -1.48). As expected, when treated with pregabalin, the placebo patients had a significantly greater improvement in pain and sleep scores than the pregabalin-treated group during the open label portion of the study (p=0.043 and 0.024 respectively). Conclusion: Pregabalin effectively ameliorated abdominal pain and improved sleep parameters in women with documented adhesions. Our data suggests that a larger trial is warranted to further assess the role of pregabalin for treatment of adhesion-mediated abdominal pain. This research was supported by an industry grant from Pfizer.