TY - JOUR T1 - Effectiveness, cost-effectiveness and safety of gabapentin versus placebo as an adjunct to multimodal pain regimens in surgical patients: protocol of a placebo controlled randomised controlled trial with blinding (GAP study) JF - BMJ Open JO - BMJ Open DO - 10.1136/bmjopen-2020-041176 VL - 10 IS - 11 SP - e041176 AU - Sarah Baos AU - Chris A Rogers AU - Reyad Abbadi AU - Aiman Alzetani AU - Gianluca Casali AU - Nilesh Chauhan AU - Laura Collett AU - Lucy Culliford AU - Samantha E de Jesus AU - Mark Edwards AU - Nicholas Goddard AU - Jennifer Lamb AU - Holly McKeon AU - Mat Molyneux AU - Elizabeth A Stokes AU - Sarah Wordsworth AU - Ben Gibbison AU - Maria Pufulete Y1 - 2020/11/01 UR - http://bmjopen.bmj.com/content/10/11/e041176.abstract N2 - Introduction Gabapentin is an antiepileptic drug currently licensed to treat epilepsy and neuropathic pain but has been used off-label to treat acute postoperative pain. The GAP study will compare the effectiveness, cost-effectiveness and safety of gabapentin as an adjunct to standard multimodal analgesia versus placebo for the management of pain after major surgery.Methods and analysis The GAP study is a multicentre, double-blind, randomised controlled trial in patients aged 18 years and over, undergoing different types of major surgery (cardiac, thoracic or abdominal). Patients will be randomised in a 1:1 ratio to receive either gabapentin (600 mg just before surgery and 600 mg/day for 2 days after surgery) or placebo in addition to usual pain management for each type of surgery. Patients will be followed up daily until hospital discharge and then at 4 weeks and 4 months after surgery. The primary outcome is length of hospital stay following surgery. Secondary outcomes include pain, total opioid use, adverse health events, health related quality of life and costs.Ethics and dissemination This study has been approved by the Research Ethics Committee . Findings will be shared with participating hospitals and disseminated to the academic community through peer-reviewed publications and presentation at national and international meetings. Patients will be informed of the results through patient organisations and participant newsletters.Trial registration number ISRCTN63614165. ER -