Frontier mental health research: psychedelics & drug studies

Each month our editorial team sifts through hundreds of papers and curates notable findings—for practitioners and informed readers who want to stay current with the evidence. Subscribe to the monthly Research Digest for expert analysis and concise summaries of key papers.

13 papers

Anxiety

Based on 52 papers

Research points to two clear groups of treatments for anxiety. First, ordinary approaches like exercise — especially walking and other regular physical activity — have strong, high-quality evidence showing medium-sized reductions in anxiety symptoms. These are proven in many randomized trials and reviews. Second, newer substance-assisted therapies (often called psychedelic‑assisted therapy) are promising. Small clinical trials and reviews show reductions in anxiety and related problems after carefully supervised doses of drugs such as psilocybin, MDMA, ketamine, and ayahuasca. However, these drug approaches are mostly early-stage or done in special research settings and need more, larger trials before they can become routine care. People thinking about or treating anxiety should know that drug‑assisted therapies are almost always given together with serious psychological support. How the drug is given, the preparation before it, and follow-up therapy matter a lot. There are also safety and equity issues to watch: some psychedelics can have rare lasting side effects, many studies are small, and people of color have been underrepresented in trials. For now, exercise has the clearest and broadest evidence. Other treatments are promising but still need more testing and careful medical oversight.

Key findings

  • Many high-quality reviews find regular physical activity reduces anxiety by a medium amount across many trials. 8792
  • Walking specifically lowers anxiety symptoms compared with doing nothing, based on 26 randomized trials pooled together. 8785
  • Clinical trials and reviews report that psychedelic-assisted therapies (drugs given with therapy) reduced anxiety symptoms in people diagnosed with anxiety disorders. 15068 15063 15056
  • For post‑traumatic stress disorder (a trauma-related anxiety condition), MDMA given with psychotherapy produced large benefits in several controlled trials. 15063
  • Psychedelic drugs appear to change the brain in ways that could help anxiety and mood problems. Lab and imaging studies report increased brain plasticity (the brain’s ability to form new connections) and changes in inflammation and brain networks after substances like psilocybin, DMT, and other psychedelics. 15132 15050 15091 15135
  • Ketamine produces fast antidepressant effects and has been tested as an alternative to electroconvulsive therapy; it has also been studied for anxiety-related conditions in some trials. 10149 10160 15068
  • Most studies of psilocybin and other classic psychedelics are small and done with close medical and psychological support, so experts say larger, well‑controlled trials are still needed before routine use. 15056 15078
  • How people are prepared and supported matters a lot: many guides and reviews agree that screening, setting expectations, building trust, and follow‑up therapy are core parts of substance‑assisted psychotherapy. 15065 15092 15063
  • People of color were underrepresented in many psychedelic-assisted psychotherapy studies, which limits how well the results apply to different ethnic groups. 15095
  • There are risks to be aware of: rare but long-lasting perceptual problems (called HPPD) and other psychological or physical side effects have been reported after hallucinogen use, so safety monitoring is important. 15048 15087

Effectiveness of physical activity interventions for improving depression, anxiety and distress: an overview of systematic reviews

Ben Singh, Tim Olds, Rachel Curtis, Dorothea Dumuid, Rosa Virgara, Amanda Watson, et al.
PubMed Summary & key facts 2023 784 citations

This umbrella review pooled evidence from 97 systematic reviews (1,039 randomized trials, 128,119 participants) to examine whether physical activity affects symptoms of depression, anxiety and psychological distress in adults. Overall, physical activity produced medium-sized reductions in symptoms (median effect size for depression = -0.43, for anxiety = -0.42; distress effect…

Behavioral Health and Interventions Eating Disorders and Behaviors Physical Activity and Health

Treatment‐resistant depression: definition, prevalence, detection, management, and investigational interventions

Roger S. McIntyre, Mohammad Alsuwaidan, Bernhard T. Baune, Michael Berk, Koen Demyttenaere, Joseph F. Goldberg, et al.
World Psychiatry Summary & key facts 2023 586 citations

Treatment-resistant depression means depression that does not get better after usual treatments. Scientists do not all agree on one clear definition, which makes it hard to know exactly how common it is or which treatments work best. Using the definition that regulators often use, about 30% of people with depression…

Electroconvulsive Therapy Studies Transcranial Magnetic Stimulation Studies Treatment of Major Depression Ketamine

Management of Treatment-Resistant Depression: Challenges and Strategies

Daphne Voineskos, Zafiris J. Daskalakis, Daniel M. Blumberger

This paper is a careful review of research about treatment-resistant depression. The authors looked through medical studies to see how doctors define this kind of depression, what makes it hard to assess, and which treatments have been tried. They describe drug strategies like adding lithium or thyroid hormone, switching antidepressant…

Electroconvulsive Therapy Studies Treatment of Major Depression Tryptophan and brain disorders Ketamine Psilocybin

Ketamine versus ECT for Nonpsychotic Treatment-Resistant Major Depression

Amit Anand, Sanjay J. Mathew, Gerard Sanacora, James W. Murrough, Fernando S. Goes, Murat Altinay, et al.
New England Journal of Medicine Summary & key facts 2023 233 citations

Researchers ran a clinical trial that directly compared ketamine treatment with electroconvulsive therapy (ECT) in people whose major depression had not improved with other treatments and who did not have psychosis. The trial found that ketamine was “noninferior” to ECT, which means ketamine worked at least as well as ECT…

Electroconvulsive Therapy Studies Treatment of Major Depression Tryptophan and brain disorders Ketamine

Psychedelic medicine: a re-emerging therapeutic paradigm

Kenneth W. Tupper, Evan Wood, Richard Yensen, Matthew W. Johnson

Researchers around the world have started clinical studies again to see if psychedelic drugs can help treat serious mental health problems. This work picks up after research that stopped around the 1950s. Scientists are running controlled studies to test whether these substances can safely reduce problems like depression, anxiety, addiction…

Chemical synthesis and alkaloids Neurotransmitter Receptor Influence on Behavior Psychedelics and Drug Studies Ketamine LSD

The relevance of ‘mixed anxiety and depression’ as a diagnostic category in clinical practice

Hans‐Jürgen Möller, Borwin Bandelow, Hans‐Peter Volz, Utako Birgit Barnikol, Erich Seifritz, Siegfried Kasper

This paper looks at whether 'mixed anxiety and depressive disorder' should be an official diagnosis. That label describes people who have both anxiety and depression symptoms that are real and limiting, but not strong enough to count as a full disorder on their own. The authors review studies that support…

Anxiety, Depression, Psychometrics, Treatment, Cognitive Processes Child and Adolescent Psychosocial and Emotional Development Psychosomatic Disorders and Their Treatments

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

Post-Psychedelic Reductions in Experiential Avoidance Are Associated With Decreases in Depression Severity and Suicidal Ideation

Richard J. Zeifman, Anne Catherine Wagner, Ros Watts, Hannes Kettner, Lea J. Mertens, Robin Carhart‐Harris
Frontiers in Psychiatry Summary & key facts 2020 101 citations

Researchers followed two groups of people who planned to use a psychedelic. They gave questionnaires before the trip, then about two weeks and four weeks after. On average, people reported less avoidance of painful thoughts and feelings, lower depression scores, and less thinking about suicide after using a psychedelic. The…

Chemical synthesis and alkaloids Neurotransmitter Receptor Influence on Behavior Psychedelics and Drug Studies Other

The Diagnosis and Management of Bipolar I and II Disorders: Clinical Practice Update

William V. Bobo
Mayo Clinic Proceedings Summary & key facts 2017 90 citations

This 2017 clinical review explains how bipolar I and II disorders are diagnosed and treated. It says bipolar illness involves swings between manic (or hypomanic) and depressive episodes. Treatment usually needs both medicines and psychosocial therapy, and care must be adjusted over time because relapses and incomplete responses — especially…

Bipolar Disorder and Treatment Electroconvulsive Therapy Studies Schizophrenia research and treatment

Psychedelic Mushrooms in the USA: Knowledge, Patterns of Use, and Association With Health Outcomes

Richard Matzopoulos, Robert Morlock, Amy Morlock, Bernard Lerer, Leonard Lerer
Frontiers in Psychiatry Summary & key facts 2022 41 citations

Researchers ran a national online survey of U.S. adults from November 2020 to March 2021 that was weighted to represent the adult population. They asked about use of psychedelic mushrooms (psilocybin), reasons for use, and mental health. Many users said they took mushrooms for general mental health and well-being. Users…

Biochemical Analysis and Sensing Techniques Chemical synthesis and alkaloids Psychedelics and Drug Studies Psilocybin

RETRACTED ARTICLE: ArticleNoteRapid and sustained antidepressant effects of intravenous ketamine in treatment-resistant major depressive disorder and suicidal ideation: a randomized clinical trial

Ahmad Zolghadriha, Afagh Anjomshoaa, Mohammad Jamshidi, Farnaz Taherkhani
BMC Psychiatry Summary & key facts 2024 20 citations

This paper reported a small, randomized trial of 64 people with treatment-resistant major depression who were given a single intravenous dose of ketamine or a saline placebo. The authors said depression and suicidal thoughts dropped quickly — within an hour — and that benefits lasted up to two months, but…

Mental Health Research Topics Treatment of Major Depression Tryptophan and brain disorders Ketamine

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
Summaries and links are for general information and education only. They are not a substitute for reading the original publication or for professional medical, legal, or other advice. Always refer to the linked source for the full study.