Ketamine as a Bridge Therapy: Reducing Acute Suicidality in Hospital Settings

Suicide rates are rising, and standard antidepressant medications (SSRIs) take 2–6 weeks to work, leaving a 1–3 month danger zone of high risk. Ketamine, a fast-acting NMDA receptor antagonist, works through the mTORC1 pathway to relieve depressive symptoms much more quickly, potentially eliminating this lag. This review proposes a hypothetical Bridge Protocol using a controlled, supervised subanesthetic dose of ketamine in a clinical setting, which the literature suggests has low addiction risk. However, the framework remains untested, and rigorous longitudinal studies are needed before widespread adoption.

Study at a glance

Abstract

This narrative literature review explores the clinical use of Ketamine as part of an untested hypothetical model framework for bridge therapy for acute suicidality. Long-term suicide rates continue to increase in the United States and in many other countries, creating a pressing public health challenge with a variety of treatment considerations. Existing standard-of-care SSRI therapeutics have a delay between administration and symptom relief at 2-6 weeks, leaving a so-called danger zone of about 1-3 months of risk for suicidal follow-through behaviors. Ketamine, a potent NMDA (N-methyl-D-aspartate) receptor antagonist, has recently seen widespread interest in both regulatory and clinical settings for increasing neuroplasticity and alleviating depressive symptoms. Ketamine's mechanism-of-action through mTORC1 is much faster than SSRI's downstream transcriptional regulation, leading to quicker relief of suicidal symptoms and the removal of the danger zone lag period. The current literature suggests that a controlled, supervised subanesthetic dose of Ketamine in a clinical setting has low risks of addiction or abuse, distinguishing therapeutic uses of Ketamine from recreational uses. While the biological efficacy of Ketamine is established, this conceptual review focuses on a possible initial hypothetical framework of a "Bridge Protocol." We searched PubMed, Google Scholar, The Cochrane Library, and PsycINFO (January 2000-December 2025) to synthesize evidence regarding SSRI latency, acute Ketamine protocols, and post-discharge safety. We conclude that while promising, the proposed Ketamine Bridge Therapy requires rigorous longitudinal validation and sustained clinical studies before it can be safely used and experience widespread adoption.