Ketamine For Suicidal Ideation

Depression is a debilitating disorder that affects 12-20% of population and is among the top five leading causes of burden of disease worldwide (Kruijshaar ME 2005). Suicide associated with depression and other psychiatric disorders is a pervasive public health problem and results in almost one million deaths per year. Unfortunately, current treatments for severe depression have limited efficacy for suicidality, specifically due to the slow time course of change in suicidal thoughts. Recently ketamine, a glutamate-modulating agent, was shown to have antidepressant and anti-suicidal effect in outpatient depressed patients. The proposed study will test the ability of a single sub-anesthetic intravenous (IV) dose of the glutamate NMDA receptor antagonist, ketamine, to provide rapid decrease in suicidal ideation (SI) in patients hospitalized with SI. In this randomized parallel-arm placebo controlled trial, ketamine is compared to midazolam, which is expected to mimic some of the acute subjective effects of ketamine but not have any sustained antidepressant effects. Specific Aim 1: To determine feasibility and tolerability of a single low-dose IV infusion of ketamine in patients with prominent SI and elevated risk for suicide. Hypothesis 1: Ketamine administration will be feasible and well tolerated in patients admitted to a psychiatric hospital with SI. Specific Aim 2: To test the efficacy of a single IV dose of ketamine, compared to an anesthetic control condition (midazolam), to rapidly reduce SI in a controlled hospital setting. Hypothesis 2: Ketamine will be associated with significant and rapid reductions in SI and depressive symptoms within 24 hours. This study will test the rapid anti-suicidal effect of a single IV dose of the N-methyl-D-aspartate (NMDA) glutamate receptor antagonist ketamine in suicidality compared with the clinical response to a single IV dose of the short-acting benzodiazepine midazolam. Midazolam is able to induce transient neuropsychiatric effects mimicking ketamine and therefore is expected to protect the integrity of the blind. Participants will continue to receive standard treatment for their psychiatric condition throughout the trial. This unique "proof-of-concept" study in suicidal patients will be conducted over three-year period.