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.

1 paper

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

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

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