SynthesisThe international journal of neuropsychopharmacology2016
Effects of Low-Dose and Very Low-Dose Ketamine among Patients with Major Depression: a Systematic Review and Meta-Analysis.
Synthesis in The international journal of neuropsychopharmacology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 97 papers, 9 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
97 citing papers in PubMed, 9 syntheses or guidelines pooled it.
- Efficacy and safety of ketamine and esketamine for unipolar and bipolar depression: an overview of systematic reviews with meta-analysis.Frontiers in psychiatry · 2024Pooled it
- International pooled patient-level meta-analysis of ketamine infusion for depression: In search of clinical moderators.Molecular psychiatry · 2022Pooled it
- Efficacy and safety of racemic ketamine and esketamine for depression: a systematic review and meta-analysis.Expert opinion on drug safety · 2022Pooled it
- Brain Changes Associated With Long-Term Ketamine Abuse, A Systematic Review.Frontiers in neuroanatomy · 2022Pooled it
- Efficacy of ketamine for major depressive episodes at 2, 4, and 6-weeks post-treatment: A meta-analysis.Psychopharmacology · 2021Pooled it
- Influence of formulation and route of administration on ketamine's safety and tolerability: systematic review.European journal of clinical pharmacology · 2021Pooled it
- The Canadian Network for Mood and Anxiety Treatments (CANMAT) Task Force Recommendations for the Use of Racemic Ketamine in Adults with Major Depressive Disorder: Recommandations Du Groupe De Travail Du Réseau Canadien Pour Les Traitements De L'humeur Et De L'anxiété (Canmat) Concernant L'utilisation De La Kétamine Racémique Chez Les Adultes Souffrant De Trouble Dépressif Majeur.Canadian journal of psychiatry. Revue canadienne de psychiatrie · 2021Pooled it
- Efficacy of single and repeated administration of ketamine in unipolar and bipolar depression: a meta-analysis of randomized clinical trials.Pharmacological reports : PR · 2020Pooled it
- The CINP Guidelines on the Definition and Evidence-Based Interventions for Treatment-Resistant Bipolar Disorder.The international journal of neuropsychopharmacology · 2020Pooled it
- Oral Prolonged-Release Ketamine for Treatment-Resistant Depression: Two Randomized Clinical Trials.JAMA network open · 2026Trial
- Correlations between major depressive disorder, splenic morphology, and immune function.BMC psychiatry · 2025Trial
- Intermittent theta-burst stimulation with adjunctive D-cycloserine rapidly resolves suicidal ideation and decreases implicit association with death/suicide.Psychological medicine · 2025Trial
- Does the intensity of dissociation predict antidepressant effects 24 hours after infusion of racemic ketamine or esketamine in treatment-resistant depression? A secondary analysis from a randomized controlled trial.Trends in psychiatry and psychotherapy · 2025Trial
- Efficacy and safety of a 4-week course of repeated subcutaneous ketamine injections for treatment-resistant depression (KADS study): randomised double-blind active-controlled trial.The British journal of psychiatry : the journal of mental science · 2023Trial
- Rapid neuroplasticity changes and response to intravenous ketamine: a randomized controlled trial in treatment-resistant depression.Translational psychiatry · 2023Trial
- A Novel, Brief, Fully Automated Intervention to Extend the Antidepressant Effect of a Single Ketamine Infusion: A Randomized Clinical Trial.The American journal of psychiatry · 2022Trial
- Intravenous arketamine for treatment-resistant depression: open-label pilot study.European archives of psychiatry and clinical neuroscience · 2021Trial
- Assessment of Relationship of Ketamine Dose With Magnetic Resonance Spectroscopy of Glx and GABA Responses in Adults With Major Depression: A Randomized Clinical Trial.JAMA network open · 2020Trial
- Intraoperative ketamine for prevention of depressive symptoms after major surgery in older adults: an international, multicentre, double-blind, randomised clinical trial.British journal of anaesthesia · 2018Trial
- Dose-Related Effects of Adjunctive Ketamine in Taiwanese Patients with Treatment-Resistant Depression.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2017Trial
37 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
12 authors.
Funding
Abstract
backgroundSeveral recent trials indicate low-dose ketamine produces rapid antidepressant effects. However, uncertainty remains in several areas: dose response, consistency across patient groups, effects on suicidality, and possible biases arising from crossover trials.
methodsA systematic search was conducted for relevant randomized trials in Medline, Embase, and PsycINFO databases up to August 2014. The primary endpoints were change in depression scale scores at days 1, 3 and 7, remission, response, suicidality, safety, and tolerability. Data were independently abstracted by 2 reviewers. Where possible, unpublished data were obtained on treatment effects in the first period of crossover trials.
resultsNine trials were identified, including 201 patients (52% female, mean age 46 years). Six trials assessed low-dose ketamine (0.5 mg/kg i.v.) and 3 tested very low-dose ketamine (one trial assessed 50 mg intra-nasal spray, another assessed 0.1-0.4 mg/kg i.v., and another assessed 0.1-0.5 mg/kg i.v., intramuscular, or s.c.). At day 3, the reduction in depression severity score was less marked in the very low-dose trials (P homogeneity <.05) and among bipolar patients. In analyses excluding the second period of crossover trials, response rates at day 7 were increased with ketamine (relative risk 3.4, 95% CI 1.6-7.1, P=.001), as were remission rates (relative risk 2.6, CI 1.2-5.7, P=.02). The absolute benefits were large, with day 7 remission rates of 24% vs 6% (P=.02). Seven trials provided unpublished data on suicidality item scores, which were reduced on days 1 and 3 (both P<.01) but not day 7.
conclusionLow-dose ketamine appears more effective than very low dose. There is substantial heterogeneity in clinical response, with remission among one-fifth of patients at 1 week but most others having benefits that are less durable. Larger, longer term parallel group trials are needed to determine if efficacy can be extended and to further assess safety.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.