A preliminary naturalistic study of low-dose ketamine for depression and suicide ideation in the emergency department

Int J Neuropsychopharmacol. 2011 Sep;14(8):1127-31. doi: 10.1017/S1461145711000629. Epub 2011 May 5.


We examined the preliminary feasibility, tolerability and efficacy of single-dose, intravenous (i.v.) ketamine in depressed emergency department (ED) patients with suicide ideation (SI). Fourteen depressed ED patients with SI received a single i.v. bolus of ketamine (0.2 mg/kg) over 1-2 min. Patients were monitored for 4 h, then re-contacted daily for 10 d. Treatment response and time to remission were evaluated using the Montgomery-Asberg Depression Rating Scale (MADRS) and Kaplan-Meier survival analysis, respectively. Mean MADRS scores fell significantly from 40.4 (s.e.m.=1.8) at baseline to 11.5 (s.e.m.=2.2) at 240 min. Median time to MADRS score ≤10 was 80 min (interquartile range 0.67-24 h). SI scores (MADRS item 10) decreased significantly from 3.9 (s.e.m.=0.4) at baseline to 0.6 (s.e.m. =0.2) after 40 min post-administration; SI improvements were sustained over 10 d. These data provide preliminary, open-label support for the feasibility and efficacy of ketamine as a rapid-onset antidepressant in the ED.

Trial registration: ClinicalTrials.gov NCT09090057.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Adult
  • Antidepressive Agents / administration & dosage
  • Antidepressive Agents / adverse effects
  • Antidepressive Agents / pharmacology
  • Antidepressive Agents / therapeutic use*
  • Depressive Disorder, Major / drug therapy*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Emergency Medical Services
  • Hospitals, University
  • Humans
  • Injections, Intravenous
  • Ketamine / administration & dosage
  • Ketamine / adverse effects
  • Ketamine / pharmacology
  • Ketamine / therapeutic use*
  • Male
  • Middle Aged
  • Pilot Projects
  • Psychiatric Status Rating Scales
  • Suicidal Ideation*
  • Time Factors
  • Young Adult


  • Antidepressive Agents
  • Ketamine

Associated data

  • ClinicalTrials.gov/NCT09090057