The Acute Antisuicidal Effects of Single-dose Intravenous Ketamine and Intranasal Esketamine in Individuals with Major Depression and Bipolar Disorders: A Systematic Review and Meta-analysis

Abstract The efficacy of ketamine in reducing suicidal ideation (SI) has been previously reported. We aimed to evaluate acute anti-SI effects of single-dose ketamine in different formulations/routes of administration by pooling results from randomized controlled trials (RCTs). A systematic search was conducted on Cochrane, Embase, Medline, and PubMed from inception to July 1st, 2020. Studies were selected based on pre-determined eligibility criteria. Effect sizes of different formulations/routes at various time points were computed using random-effects models. With data from nine eligible RCTs (n=197), the pooled effect size for anti-SI effects at 24-hour time point was 1.035 (N=6, CI: 0.793 to 1.277, p