The Role of Ketamine in Treatment-resistant Depression: A Narrative Review

Ketamine, a non-competitive N-methyl-D-aspartate receptor antagonist, has emerged as an effective therapeutic agent for the management of treatment-resistant depression. Repeated treatments with ketamine show rapid, robust, and sustained antidepressant effects. Despite the large body of evidence, key concerns include adverse effects such as dissociative symptoms, hemodynamic instability, and the risk of abuse with long-term ketamine therapy. This narrative review provides an overview of the neurobiological mechanisms underlying ketamine’s antidepressant effects, its basic pharmacodynamics, and its safety profile. The clinical evidence regarding ketamine’s efficacy in depression is also summarized, and the need for further research on the long-term effects of ketamine therapy, the development of agents with similar antidepressant effects but fewer adverse effects or potential for abuse, and the identification of biomarkers to predict the response to ketamine is highlighted.