The effect of intravenous, intranasal, and oral ketamine in mood disorders: A meta-analysis.
Journal of Affective Disorders November 1, 2020 R. Mcintyre, Isabelle P. Carvalho, L. Lui et al. 186 citations
Ketamine is a rapid and effective treatment for adults with treatment-resistant depression, but different formulations and routes of delivery vary in effect size. A meta-analysis of studies found that intranasal ketamine or esketamine had a large effect on depression symptoms at 24 hours and again at 7-20 days. Intravenous ketamine or esketamine showed a large but not statistically significant effect at 2-6 days. Oral ketamine had a moderate effect at 21-28 days. No conclusions about which formulation or route is best could be drawn because direct comparisons are lacking. More studies with larger samples are needed, especially for oral ketamine.