February 2026
Depression
What February 2026's 25 new studies found, synthesized from the papers below. All Depression research →
The synthesis
Synthesized from 25 studies in the library · AI-generated, grounded in the abstracts below
Found by searching the library for Depression, major depressive disorder, MDD, depressive disorder, treatment-resistant depression, then ranked by relevance.
Research published in February 2026 indicates that ketamine and esketamine consistently produce rapid, short-term antidepressant effects in treatment-resistant depression, with some evidence of benefit in special populations and older adults, though long-term safety and maintenance remain understudied. Psychedelic-assisted therapies (psilocybin, DMT) show promising acute and sustained effects in some trials, but microdosing psilocybin did not outperform placebo, and mindfulness-based interventions yield moderate improvements in depression. Overall, findings are mixed and limited by small samples, open-label designs, and lack of long-term data.
Evidence by study
Direction is which way each study's own result points, not our rating of the study.
What the directions mean
- Supports:
- the study found the intervention worked, or its hypothesis held.
- Opposes:
- it found the opposite, no benefit or a harm.
- No effect:
- no significant difference either way.
- Mixed:
- effects in both directions within the same study.
- Unclear:
- the abstract does not report a direction.
| Study | Design | Sample size | Direction | Finding |
|---|---|---|---|---|
| A Mixed Methods Study on the Effects of a Compassion Meditation Program on Ego Integrity and Depression among Older Adults 2026 | mixed-methods study | 10 | Supports | A compassion meditation program significantly reduced isolation and depression and promoted ego-integrity and self-kindness in older adults. |
| Ketamine and Esketamine Therapy in Affective Disorders: A Comprehensive Review of Mechanisms, Clinical Evidence, Safety, and Future Directions 2026 | review | Supports | Ketamine and esketamine provide rapid antidepressant effects for treatment-resistant depression, but long-term safety and maintenance strategies require further study. | |
| Ketamine pharmacotherapy for major depressive disorder: A narrative review 2026 | narrative review | Mixed | Ketamine and esketamine show mixed-to-positive antidepressant effects in treatment-resistant depression and MDD with suicidal ideation, with non-inferiority to established treatments. | |
| The Effects of Mindfulness Techniques on Anxiety, Depression, and Stress, with an Emphasis on Gratitude: A Systematic Review and Meta-Analysis 2026 | systematic review with meta-analysis | 24000 | Supports | Mindfulness-Based Interventions produced a moderate improvement in psychological outcomes (Hedges' g = −0.45), with stronger effects for anxiety (g = −0.56) than depression (g = −0.45). |
| A phase 2 uncontrolled, open-label study of intranasal BPL-003 (5-methoxy- N,N -dimethyltryptamine) in patients with treatment-resistant depression 2026 | clinical trial | Supports | A single dose of BPL-003 produced a rapid and sustained reduction in MADRS score over 12 weeks in people with treatment-resistant depression. | |
| Psilocybin for psychiatric disorders: History, clinical trials, neuroimaging, and regulations 2026 | review | Supports | Psilocybin shows therapeutic potential for major depressive disorder, depressive symptoms in life-threatening illnesses, and some substance use disorders, but larger blinded trials and standardized protocols are needed. | |
| Predictors of the Effectiveness of Psychedelics in Treating Depression—A Scoping Review 2026 | scoping review | 48 | Supports | Antidepressant response in psychedelic-assisted therapies is driven less by static patient characteristics and more by in-session experiences and contextual factors such as therapeutic alliance and music. |
| Traditional Buddhist Mindfulness versus Secular Mindfulness-based Cognitive Therapy for Residual Depressive Symptoms in Patients Treated for Depressive Disorder: A Pilot Randomized Controlled Trial 2026 | pilot randomized controlled trial | Supports | Both traditional Buddhist mindfulness and secular MBCT reduced residual depressive symptoms, with no significant difference between the two interventions. | |
| KET-MCI: A Pilot Safety and Tolerability Study of Single Infusion Intravenous Ketamine for Older Adults with Depression and Mild Cognitive Impairment 2026 | open-label clinical trial | 13 | Supports | A single ketamine infusion was safe and well tolerated in patients with MCI-D and was associated with large-magnitude improvements in depression severity at 24 hours, with persistent benefit in 8 of 13 patients up to one month. |
| Safety and Efficacy of Microdosing Psilocybin over 8 Weeks for Major Depressive Disorder: A Randomized Clinical Trial 2026 | randomized controlled trial | 39 | No effect | Repeated low doses of psilocybin did not demonstrate statistically greater efficacy than placebo for reducing depressive symptoms in adults with major depressive disorder. |
| Multiple peripheral inflammatory markers in adolescents with major depressive disorder treated with repeated esketamine infusions: results from a randomized controlled trial. 2026 | randomized controlled trial | Unclear | Repeated esketamine infusions were associated with changes in peripheral inflammatory markers in adolescents with major depressive disorder. | |
| Integrating Psychiatric, Psychotherapeutic, and Nursing Care in Intranasal Esketamine for Treatment-Resistant Depression 2026 | narrative review | Supports | A structured phase-based multidisciplinary framework integrating psychiatry, nursing, and psychotherapy may support safer, more acceptable delivery of intranasal esketamine and potentially improve retention and patient experience, but prospective studies are needed. | |
| The use of repetitive transcranial magnetic stimulation (rTMS), electroconvulsive therapy (ECT), ketamine, and esketamine in reducing suicidality in major depressive disorder: A comprehensive narrative review 2026 | narrative review | Supports | Ketamine, esketamine, rTMS, and ECT are associated with reductions in suicidal ideation in people with major depressive disorder, with the strongest evidence supporting rapid, short-term effects for ketamine and esketamine. | |
| Ketamine as a Mental Health Treatment 2026 | review | Supports | Ketamine and esketamine offer a novel mechanism for treatment-resistant mental health disorders, but their use is marked by fragmented regulation and evolving evidence. | |
| Mental health outcomes following a psilocybin session within Oregon’s state-regulated model: A naturalistic study 2026 | naturalistic study | 88 | Supports | Psilocybin sessions under Oregon's regulatory model were associated with significant improvements in depression, anxiety, and well-being 30 days post-session, with no persistent hallucinogen persisting perception disorder at 30 days. |
| Sex differences in placebo and antidepressant response to intranasal esketamine for treatment-resistant depression 2026 | pooled analysis of randomized, double-blind, placebo-controlled trials | Mixed | Females showed greater overall improvement and higher odds of treatment response than males toward the end of the trials, while males showed a significant reduction in sadness symptoms after esketamine on day 2. | |
| LSD microdosing for major depressive disorder: Mood and pharmacokinetic outcomes from a Phase 2a trial 2026 | clinical trial | Supports | Short-term mood improvements followed microdosed LSD in people with depression, with no tolerance or sensitisation observed despite dose titration. | |
| Ketamine or Esketamine in Special Populations of Patients With Treatment-Resistant Depression 2026 | review | Supports | Both ketamine and esketamine demonstrate efficacy in multiple treatment-resistant depression subpopulations, including geriatric, psychiatric, neurologic, oncologic, pediatric, and obstetric patients. | |
| The effect and neural changes underlying mindfulness meditation training in patients with comorbid internet gaming disorder and depression: A randomized clinical trial. 2026 | randomized controlled trial | 70 | Supports | Mindfulness meditation reduced depression, addiction, and cravings more than progressive muscle relaxation in patients with IGD-D, and altered functional connectivity in brain networks linked to control and emotion regulation. |
| The Antioxidant Activity of Ketamine: Threshold-Dependent Mechanism in Treatment-Resistant Depression? 2026 | in vitro experimental study | Supports | Ketamine at 25 ng/mL increased viability of HT22 cells under oxidative stress induced by 1000 µM H₂O₂, but not at lower H₂O₂ concentrations. | |
| A short-acting psychedelic intervention for major depressive disorder: a phase IIa randomized placebo-controlled trial. 2026 | randomized controlled trial | 34 | Supports | A single dose of DMT with psychotherapeutic support produced a rapid, significant reduction in depressive symptoms sustained up to 3 months. |
| Microdosing psilocybin for major depressive disorder: study protocol for a phase II double-blind placebo-controlled randomised partial crossover trial 2026 | phase II, double-blind, placebo-controlled, randomised partial crossover trial | 40 | Unclear | The trial's primary outcome—change in depression symptoms after four weeks of microdosing psilocybin versus placebo—has not yet been reported, as this is a study protocol. |
| ADVERSE EFFECTS OF ESKETAMINE IN TREATMENT RESISTANT DEPRESSION: A COMPREHENSIVE LITERATURE REVIEW (2020-2025) 2026 | systematic review | Supports | Under proper clinical supervision, esketamine shows an acceptable safety profile with most adverse effects being temporary and mild to moderate, and long-term studies up to 6.5 years found no evidence of organ damage, cognitive decline, or meaningful abuse problems. | |
| Does number of dosing sessions and type of adjunctive psychotherapy affect outcomes in psychedelic-assisted-psychotherapy for depressive disorders and anxiety disorders? A systematic review and meta-analysis. 2026 | systematic review and meta-analysis | 23 | Supports | Psychedelic-assisted psychotherapy produced large to very large effects on depression and anxiety symptoms, with some evidence that two dosing sessions may be more effective than one, though this finding was not robust across analyses. |
| Ketamine ameliorates postpartum depression-like behaviors in rats exposed to sevoflurane during pregnancy through the AMPK/SIRT1/NLRP3 pathway. 2026 | animal experiment | Supports | Repeated sevoflurane exposure during mid-gestation induces depression-like behaviors in postpartum rats, and ketamine alleviates these behaviors by reducing microglial neuroinflammation and NLRP3 inflammasome activation via the AMPK/SIRT1 signaling pathway. |
A compassion meditation program significantly reduced isolation and depression and promoted ego-integrity and self-kindness in older adults.
mixed-methods study Sample size: 10
Ketamine and esketamine provide rapid antidepressant effects for treatment-resistant depression, but long-term safety and maintenance strategies require further study.
review
Ketamine and esketamine show mixed-to-positive antidepressant effects in treatment-resistant depression and MDD with suicidal ideation, with non-inferiority to established treatments.
narrative review
Mindfulness-Based Interventions produced a moderate improvement in psychological outcomes (Hedges' g = −0.45), with stronger effects for anxiety (g = −0.56) than depression (g = −0.45).
systematic review with meta-analysis Sample size: 24000
A single dose of BPL-003 produced a rapid and sustained reduction in MADRS score over 12 weeks in people with treatment-resistant depression.
clinical trial
Psilocybin shows therapeutic potential for major depressive disorder, depressive symptoms in life-threatening illnesses, and some substance use disorders, but larger blinded trials and standardized protocols are needed.
review
Antidepressant response in psychedelic-assisted therapies is driven less by static patient characteristics and more by in-session experiences and contextual factors such as therapeutic alliance and music.
scoping review Sample size: 48
Both traditional Buddhist mindfulness and secular MBCT reduced residual depressive symptoms, with no significant difference between the two interventions.
pilot randomized controlled trial
A single ketamine infusion was safe and well tolerated in patients with MCI-D and was associated with large-magnitude improvements in depression severity at 24 hours, with persistent benefit in 8 of 13 patients up to one month.
open-label clinical trial Sample size: 13
Repeated low doses of psilocybin did not demonstrate statistically greater efficacy than placebo for reducing depressive symptoms in adults with major depressive disorder.
randomized controlled trial Sample size: 39
Repeated esketamine infusions were associated with changes in peripheral inflammatory markers in adolescents with major depressive disorder.
randomized controlled trial
A structured phase-based multidisciplinary framework integrating psychiatry, nursing, and psychotherapy may support safer, more acceptable delivery of intranasal esketamine and potentially improve retention and patient experience, but prospective studies are needed.
narrative review
Ketamine, esketamine, rTMS, and ECT are associated with reductions in suicidal ideation in people with major depressive disorder, with the strongest evidence supporting rapid, short-term effects for ketamine and esketamine.
narrative review
Ketamine and esketamine offer a novel mechanism for treatment-resistant mental health disorders, but their use is marked by fragmented regulation and evolving evidence.
review
Psilocybin sessions under Oregon's regulatory model were associated with significant improvements in depression, anxiety, and well-being 30 days post-session, with no persistent hallucinogen persisting perception disorder at 30 days.
naturalistic study Sample size: 88
Females showed greater overall improvement and higher odds of treatment response than males toward the end of the trials, while males showed a significant reduction in sadness symptoms after esketamine on day 2.
pooled analysis of randomized, double-blind, placebo-controlled trials
Short-term mood improvements followed microdosed LSD in people with depression, with no tolerance or sensitisation observed despite dose titration.
clinical trial
Both ketamine and esketamine demonstrate efficacy in multiple treatment-resistant depression subpopulations, including geriatric, psychiatric, neurologic, oncologic, pediatric, and obstetric patients.
review
Mindfulness meditation reduced depression, addiction, and cravings more than progressive muscle relaxation in patients with IGD-D, and altered functional connectivity in brain networks linked to control and emotion regulation.
randomized controlled trial Sample size: 70
Ketamine at 25 ng/mL increased viability of HT22 cells under oxidative stress induced by 1000 µM H₂O₂, but not at lower H₂O₂ concentrations.
in vitro experimental study
A single dose of DMT with psychotherapeutic support produced a rapid, significant reduction in depressive symptoms sustained up to 3 months.
randomized controlled trial Sample size: 34
The trial's primary outcome—change in depression symptoms after four weeks of microdosing psilocybin versus placebo—has not yet been reported, as this is a study protocol.
phase II, double-blind, placebo-controlled, randomised partial crossover trial Sample size: 40
Under proper clinical supervision, esketamine shows an acceptable safety profile with most adverse effects being temporary and mild to moderate, and long-term studies up to 6.5 years found no evidence of organ damage, cognitive decline, or meaningful abuse problems.
systematic review
Psychedelic-assisted psychotherapy produced large to very large effects on depression and anxiety symptoms, with some evidence that two dosing sessions may be more effective than one, though this finding was not robust across analyses.
systematic review and meta-analysis Sample size: 23
Repeated sevoflurane exposure during mid-gestation induces depression-like behaviors in postpartum rats, and ketamine alleviates these behaviors by reducing microglial neuroinflammation and NLRP3 inflammasome activation via the AMPK/SIRT1 signaling pathway.
animal experiment
Points of agreement
- Ketamine and esketamine consistently show rapid antidepressant effects in treatment-resistant depression across multiple reviews and trials.
- Psychedelic-assisted therapies (psilocybin, DMT) show significant improvements in depressive symptoms in several trials and reviews.
- Mindfulness-based interventions produce moderate reductions in depressive symptoms.
- Safety profiles for ketamine/esketamine are generally acceptable under supervision, with transient adverse effects.
Conflicts
- Microdosing psilocybin showed no significant benefit over placebo in one RCT, while other psychedelic trials (full-dose) showed positive effects.
- Some reviews report mixed-to-positive effects for ketamine, while others report positive effects consistently.
- Sex differences in esketamine response: females showed greater overall improvement, but males showed early sadness reduction, indicating potential differential effects.
Gaps
- Long-term durability of antidepressant effects for ketamine, esketamine, and psychedelics remains understudied.
- Most psychedelic trials are small, open-label, or lack blinded assessments.
- Microdosing studies are limited and show conflicting results; more controlled trials needed.
- Special populations (geriatric, pediatric, obstetric) lack large-scale randomized controlled trials.
- Standardized protocols for psychedelic-assisted psychotherapy are needed.
- Long-term safety data for psychedelics, including HPPD and cognitive effects, are limited.