Frontier mental health research: psychedelics & drug studies

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6 papers

Sadness or low mood

Based on 75 papers

Research shows several different ways can help with sadness or low mood. Right now, the strongest clinical evidence for a fast-acting drug comes from ketamine and its approved form esketamine. At the same time, a wave of studies on classic psychedelics (psilocybin, LSD, DMT) and entactogens (MDMA) looks promising, especially when the drug is given together with careful psychological support. However, most psychedelic studies are still small or early-stage. They often rely on the setting, preparation, and therapy as part of the treatment, so researchers say we need larger, controlled trials and more long-term safety data. Also, non-drug options like brain stimulation and standard psychotherapies remain important parts of treatment plans and have mixed but useful evidence.

Key findings

  • Ketamine has the strongest current clinical evidence among rapid-acting drug options for major depression. 15070
  • An intranasal form of ketamine (esketamine), given with a new oral antidepressant, produced faster and larger symptom improvements than a new antidepressant plus placebo in a randomized trial of treatment‑resistant depression. 12156
  • A direct clinical trial found ketamine treatment was at least as effective as electroconvulsive therapy (ECT) for some people with hard-to-treat nonpsychotic depression. 10160
  • Psychedelic-assisted psychotherapy (for example psilocybin, MDMA, LSD) has shown promising benefits for depression and PTSD in several trials, but most studies so far are small or early-stage and need larger, controlled follow-up studies. 15135 15056 15063 15085
  • Laboratory and early human studies suggest classic psychedelics can boost the brain’s ability to rewire (called neuroplasticity) and can reduce brain inflammation, but blood biomarkers like BDNF do not reliably reflect these brain changes yet. 15132 15050 15129
  • How the drug is given matters a lot: studies and treatment guides agree that preparation, the person’s mindset, the setting, and follow-up therapy (often called 'set, setting, and integration') shape safety and outcomes. 15065 15086 15096
  • There are real safety and equity concerns: some substances (for example ibogaine) carry serious cardiac or neurological risks, some people can develop lasting perceptual problems after hallucinogens, and people of color are often under‑represented in trials. 15085 15048 15095 15094
  • Non-drug brain treatments show mixed results. Small deep brain stimulation (DBS) studies reported large improvements in a few people with severe depression, while a large one‑year trial of vagus nerve stimulation did not show a clear difference on its main outcome but did show some secondary clinician- and patient-rated benefits. 10166 10163
  • Standard psychotherapies help many people but do not work for everyone: pooled data across trials find modest response rates for depression, and clinical guidelines recommend collaborative, personalized care and stepwise treatment plans for major depression. 12851 15076 13305
  • Combining treatments is an active research idea. Early studies suggest pairing ketamine with brain stimulation (like TMS) or combining mindfulness with psychedelic therapy may boost effects, but this is still experimental. 10162 15047

Emotion-regulation strategies across psychopathology: A meta-analytic review

Amelia Aldao, Susan Nolen–Hoeksema, Susanne Schweizer
PubMed Summary & key facts 2010 6,290 citations

This meta-analysis combined 241 effect sizes from 114 studies to test how six habitual emotion-regulation strategies relate to symptoms of anxiety, depression, eating disorders, and substance-related problems. Rumination showed the strongest (large) link with symptoms. Avoidance, problem solving, and suppression showed medium-to-large links, while reappraisal and acceptance showed smaller (small-to-medium)…

Anxiety, Depression, Psychometrics, Treatment, Cognitive Processes Child and Adolescent Psychosocial and Emotional Development Mental Health Research Topics

Green space exposure on depression and anxiety outcomes: A meta-analysis

Ziquan Liu, Xuemei Chen, Huanhuan Cui, Yuxuan Ma, Ning Gao, Xinyu Li, et al.
PubMed Summary & key facts 2023 118 citations

This meta-analysis of observational studies found that higher exposure to green space was linked with slightly lower odds of depression and possibly lower odds of anxiety. A 10% increase in the amount of green space was associated with lower odds of depression (OR 0.963; 95% CI 0.948–0.979) and with a…

Land Use and Ecosystem Services Urban Agriculture and Sustainability Urban Green Space and Health

Absolute and relative outcomes of psychotherapies for eight mental disorders: a systematic review and meta‐analysis

Pim Cuijpers, Clara Miguel, Marketa Ciharova, Mathias Harrer, Djordje Basic, Ioana A Cristea, et al.
PubMed Central (PMC) Summary & key facts 2024 107 citations

This large review combined 441 randomized trials with 33,881 patients to measure how many people show a clear response to psychotherapy across eight mental disorders. Response was defined as at least a 50% reduction in symptoms from before to after treatment. Pooled response rates were modest (for example, about 42%…

Anxiety, Depression, Psychometrics, Treatment, Cognitive Processes Psychosomatic Disorders and Their Treatments Treatment of Major Depression

Effectiveness of Digital Mental Health Tools to Reduce Depressive and Anxiety Symptoms in Low- and Middle-Income Countries: Systematic Review and Meta-analysis

Jiyeong Kim, Lois Maame Donkor Aryee, Heejung Bang, Steffi Prajogo, Yong Kyung Choi, Jeffrey S. Hoch, et al.
JMIR Mental Health Summary & key facts 2023 63 citations

The researchers did a large, careful search for studies of digital mental health tools (things like websites, phone apps, text messages, or online therapy) aimed at reducing depression and anxiety in low- and middle-income countries. They only kept randomized controlled trials, which are studies where people are randomly put into…

Digital Mental Health Interventions Impact of Technology on Adolescents Mental Health Research Topics

The Effect of Walking on Depressive and Anxiety Symptoms: Systematic Review and Meta-Analysis

Zijun Xu

This systematic review pooled 75 randomized trials with 8,636 people to see if walking changes symptoms of depression and anxiety. In adults, walking reduced depressive symptoms (SMD −0.591, 95% CI −0.778 to −0.403, P

Climate Change and Health Impacts Occupational Therapy Practice and Research Urban Green Space and Health

Effects of psychoplastogens on blood levels of brain-derived neurotrophic factor (BDNF) in humans: a systematic review and meta-analysis

Abigail E. Calder, Adrian Hase, Gregor Hasler
Molecular Psychiatry Summary & key facts 2024 10 citations

Researchers pooled results from 29 human studies that measured blood levels of a protein called brain-derived neurotrophic factor, or BDNF, after people received so-called psychoplastogen drugs such as ketamine or psychedelics. They found no clear change in blood BDNF after these drugs. The authors say this does not prove the…

Neurotransmitter Receptor Influence on Behavior Psychedelics and Drug Studies Treatment of Major Depression Ayahuasca Ketamine
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