Evaluation of Adjunctive Ketamine to Benzodiazepines for Management of Alcohol Withdrawal Syndrome

Background: Adjunctive medications to manage alcohol withdrawal syndrome (AWS) in patients not adequately responding to escalating doses of benzodiazepines (BZDs) are limited. The use of the N-methyl-d-aspartate antagonist ketamine, may serve as an effective adjunct agent; however, no published data currently exist for this practice. Objective: To determine the safety and efficacy of adjunct ketamine for management of AWS. Methods: The study was a retrospective review of adult patients from April 2011 to March 2014 who were administered ketamine specifically for management of AWS. Outcomes included changes in BZD requirements and ketamine-related adverse reactions. Results: Of 235 patients screened, 23 patients met study eligibility. Ketamine was initiated primarily with toxicology consultation for significant BZD requirements or delirium tremens. The mean time to initiation of ketamine from first treatment of AWS, and total duration of therapy were 33.6 and 55.8 hours, respectively. Mean initial infusion dose and median total infusion rate during therapy were 0.21 and 0.20 mg/kg/h, respectively. There was no change in sedation or alcohol withdrawal scores in patients within 6 hours of ketamine initiation. The median change in BZD requirements at 12 and 24 hours post–ketamine initiation were −40.0 and −13.3 mg, respectively. The mean time to AWS resolution was 5.6 days. There was one documented adverse reaction of oversedation, requiring dose reduction. Conclusions: Ketamine appears to reduce BZD requirements and is well tolerated at low doses. Prospective dose range evaluations in the management of AWS would be helpful in determining its place as an adjunctive agent.