Skip to content

Comparison of average time-to-relapse following ECT versus ketamine - A systematic review.

Minna Chang, Allan H. Young, Mario F Juruena

Journal of psychopharmacology (Oxford, England) April 16, 2026 DOI: 10.1177/02698811261430502 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics Systematic review Randomized Peer reviewed
Sample size 13
Population TRD patients
Interventions Electroconvulsive therapy Ketamine
Topics Depression Ketamine Esketamine
Keywords Antidepressant duration Electroconvulsive therapy Relapse-free time Remission duration
Key findings There is evidence for sustained therapeutic potential of both ECT and ketamine in treatment-resistant depression, with ECT possibly associated with longer remission, but no direct comparisons of time-to-relapse between the two treatments were available within the inclusion criteria.

Abstract

Previous systematic reviews and meta-analyses have reported impressive antidepressant effects of ketamine in treatment-resistant depression (TRD). While ketamine has been compared with electroconvulsive therapy (ECT), the gold standard treatment, the extent and durability of its antidepressant effects over longer periods remain unclear. To our knowledge, this is the first systematic review comparing average time-to-relapse between ECT and ketamine in TRD. To compare the average time-to-relapse between ECT and ketamine for TRD. We conducted this systematic review using PubMed, Medline, ScienceDirect, Cochrane Library, Ovid, PsycNET, Embase and Google Scholar, against predetermined criteria. CRD42025643824. Thirteen studies met inclusion criteria: 10 examined ketamine/(s)ketamine, and 3 focused on ECT. Twelve were randomised controlled trials (RCTs), and one was retrospective. Heterogeneity was observed in dosing regimens and administration schedules, with some studies having limited follow-up and small sample sizes. Findings are synthesised narratively. In summary, there is evidence for sustained therapeutic potential of both ECT and ketamine, ECT possibly being associated with longer remission. Increased dose, frequency and use of maintenance ECT/ketamine appear to prolong remission, and continuing oral antidepressants may prolong this further. It should also be noted that this review excluded studies involving psychotic depression, leading to the exclusion of some head-to-head studies, thus limiting the generalisability of the findings in these populations. There is currently a lack of studies within our inclusion criteria that directly compare time-to-relapse after ECT and ketamine, preventing formal statistical analysis. More high-quality, large-scale RCTs directly comparing these treatment modalities with longer follow-up times are needed.

Comparable studies

Other systematic reviews and meta-analyses on ketamine for depression, most cited first.

Study Year Design Participants
Ketamine and Other NMDA Antagonists: Early Clinical Trials and Possible Mechanisms in Depression Participants with major depression in placebo-controlled, double-blind, randomized... 2015 Systematic review and meta-analysis
Side-effects associated with ketamine use in depression: a systematic review. Patients with depression 2018 Systematic review
Comparative efficacy of racemic ketamine and esketamine for depression: a systematic review and meta-analysis Adults with unipolar or bipolar major depression 2020 Systematic review and meta-analysis n = 1,877
Single-dose infusion ketamine and non-ketamine N-methyl-D-aspartate receptor antagonists for unipolar and bipolar depression: a meta-analysis of efficacy, safety and time trajectories Patients with major depressive disorder or bipolar depression 2016 Systematic review and meta-analysis n = 588
The use of ketamine as an antidepressant: a systematic review and meta‐analysis People with major depressive disorder or bipolar disorder receiving ketamine infusion 2015 Meta-analysis n = 437

Explore topics

By condition and practice