Treatment of Suicidal Ideation With Intravenous Ketamine Infusion

Inclusion Criteria: 1. Age : 19-64 2. Significant suicidality score on the Columbia Suicide Severity Rating Scale (C-SSRS) 3. Willing and able to provide informed consent. 4. Individuals with current substance abuse are allowed Exclusion Criteria: 1. Pregnant or lactating; women of reproductive potential must have a negative urine pregnancy test (urine dipstick method) 2. Post-Partum state : defined as being within 2 months of delivery or miscarriage 3. Homicide risk as determined by clinical interview 4. Treatment with any medication known to specifically target the glutamate-NMDA receptor system (ie lamotrigine, acamprosate, memantine, riluzole or lithium) 5. Any known hypersensitivity or serious adverse effect associated with ketamine treatment. 6. Any clinically significant medical condition or therapy that would preclude treatment with ketamine, to include recent myocardial infarction or unstable angina 7. Medically unstable, including acute withdrawal from alcohol or benzodiazepines requiring the use of benzodiazepine treatment. 8. Any of the following DSM-IV diagnoses or categories: * Any current psychosis or history of a non-mood psychotic disorder (e.g., schizophrenia) * Currently in a manic or mixed episode * Current use (defined by urine dipstick test) or abuse of hallucinogenic drugs (except marijuana) such as phencyclidine * Any dissociative disorder * Any pervasive developmental disorder (e.g., autism) * A cognitive disorder (e.g., Alzheimer's Disease) * Cluster A personality disorder (e.g., schizoid or schizotypal); note that cluster B and C personality disorders may be included * Any eating disorder