Intravenous Ketamine in Psychiatry: Therapeutic Applications, Mechanisms of Action, and Clinical Perspectives

• DOI: https://doi.org/10.22533/at.ed.51572142603075

• Palavras-chave: Escetamine; Psychiatry; Treatment-resistant depression; Ketamine; Mental disorders; Neuroplasticity.

• Keywords: Escetamine; Psychiatry; Treatment-resistant depression; Ketamine; Mental disorders; Neuroplasticity.

• Abstract:

  Intravenous esketamine represents a significant therapeutic innovation in the field of psychiatry, particularly in the management of treatment-resistant depression and severe psychiatric conditions associated with suicidal ideation. Derived from the S-enantiomer of ketamine, esketamine acts primarily as an N-methyl-D-aspartate (NMDA) receptor antagonist, promoting rapid glutamatergic modulation and brain neuroplasticity. The present study aims to review the scientific literature on the use of intravenous esketamine in psychiatry, addressing its mechanisms of action, clinical indications, therapeutic efficacy, adverse effects, and current challenges. This is a narrative literature review conducted through the analysis of scientific articles indexed in the PubMed, Scielo, MEDLINE, and Google Scholar databases, published between 2015 and 2026, in Portuguese and English. The findings demonstrate that intravenous ketamine produces a rapid antidepressant response, with significant improvement in symptoms among patients refractory to conventional treatments. Furthermore, studies show benefits in anxiety disorders, bipolar disorder, and suicide prevention. However, adverse effects such as dissociation, transient elevation of blood pressure, nausea, and abuse potential still represent significant limitations. It is concluded that intravenous ketamine is a promising and effective alternative in contemporary psychiatry, although further long-term studies are needed to establish safe and standardized protocols.