Frontier mental health research: psychedelics & drug studies

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4 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

Synthesizing the Evidence for Ketamine and Esketamine in Treatment-Resistant Depression: An International Expert Opinion on the Available Evidence and Implementation

Roger S. McIntyre, Joshua D. Rosenblat, Charles B. Nemeroff, Gerard Sanacora, James W. Murrough, Michael Berk, et al.
American Journal of Psychiatry Summary & key facts 2021 646 citations

A group of international mood-disorder experts reviewed the research on ketamine and esketamine for adults whose depression did not get better with usual antidepressants. They found that these drugs work differently from standard antidepressants and can lift symptoms more quickly for some people with treatment-resistant depression. However, the experts also…

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

Canadian Network for Mood and Anxiety Treatments (CANMAT) 2023 Update on Clinical Guidelines for Management of Major Depressive Disorder in Adults: Réseau canadien pour les traitements de l’humeur et de l’anxiété (CANMAT) 2023 : Mise à jour des lignes directrices cliniques pour la prise en charge du trouble dépressif majeur chez les adultes

Raymond W. Lam, Sidney H. Kennedy, G. Camelia Adams, Anees Bahji, Serge Beaulieu, Venkat Bhat, et al.

The CANMAT 2023 update gives doctors clear, up-to-date advice for treating adults with major depressive disorder. It puts evidence into a practical, clinician-friendly format. The update says treatment should be a team effort between patients and clinicians, be tailored to each person, and follow a planned, systematic process with regular…

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

Efficacy and safety of a 4-week course of repeated subcutaneous ketamine injections for treatment-resistant depression (KADS study): randomised double-blind active-controlled trial

Colleen Loo, Nick Glozier, Dávid Barton, Bernhard T. Baune, Natalie Mills, Paul B. Fitzgerald, et al.

Researchers tested repeated subcutaneous (under-the-skin) injections of racemic ketamine in people whose depression had not improved after at least two antidepressant trials. People got injections twice a week for 4 weeks and neither participants nor the raters knew which drug they were getting. When the study allowed higher, response-guided ketamine…

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

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
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