Frontier mental health research: psychedelics & drug studies

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8 papers

The serotonin theory of depression: a systematic umbrella review of the evidence

Moncrieff, Joanna, Cooper, Ruth E., Stockmann, Tom, et al.
Nature Summary & key facts 2023 830 citations

This umbrella review looked at the best existing reviews and large studies to see if depression is linked to low serotonin or low serotonin activity. Across measures of serotonin in fluids, receptor and transporter studies, tryptophan depletion experiments, and large genetic studies, the evidence was mixed or absent. The authors…

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

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

Ketamine for the treatment of mental health and substance use disorders: comprehensive systematic review

Zach Walsh, Özden Merve Mollaahmetoğlu, Joseph M. Rootman, Shannon Golsof, Johanna Louise Keeler, Beth Marsh, et al.
BJPsych Open Summary & key facts 2021 168 citations

This systematic review looked at 83 published reports on ketamine for mental health and substance use disorders. It found strong evidence that ketamine can produce rapid antidepressant and anti‑suicidal effects, but these benefits tend to be short‑lived. Evidence for other conditions was weaker but often showed similar short-term effects. Many…

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

Efficacy of single and repeated administration of ketamine in unipolar and bipolar depression: a meta-analysis of randomized clinical trials

Joanna Kryst, Paweł Kawalec, Alicja Mikrut Mitoraj, Andrzej Pilc, Władysław Lasoń, Tomasz Brzostek
PubMed Summary & key facts 2020 145 citations

This meta-analysis combined 20 randomized clinical trials up to February 22, 2019, and found that a single dose of ketamine produced rapid antidepressant effects that were strongest at 24 hours and that these effects were still detectable up to 7 days. The analysis also found that repeated ketamine doses helped…

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

Ketamine Assisted Psychotherapy: A Systematic Narrative Review of the Literature

Sandra J Drozdz, Akash Goel, Matthew W McGarr, Joel Katz, Paul Ritvo, Gabriella Mattina, et al.
PubMed Summary & key facts 2022 92 citations

This systematic review looked at 17 studies with a total of 603 participants on ketamine-assisted psychotherapy (KAP). The reviewed reports say KAP can, in some cases, start and lengthen meaningful reductions in pain, anxiety, and depression, and help with rapport, treatment engagement, and abstinence for people with substance problems. However,…

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

Ketamine and psychotherapy for the treatment of psychiatric disorders: systematic review

Bess M. Kew, Richard Porter, Katie M. Douglas, Paul Glue, Charlotte L. Mentzel, Ben Beaglehole
BJPsych Open Summary & key facts 2023 51 citations

The combination of psychotherapy and ketamine offers promise for the treatment of psychiatric disorders, but study heterogeneity prevents definitive recommendations for their integration. Larger randomised controlled trials using manualised psychotherapies and standardised ketamine protocols are recommended to clarify the extent to which the addition of psychotherapy to ketamine improves outcomes…

Diet and metabolism studies Treatment of Major Depression Tryptophan and brain disorders

Is there a risk of addiction to ketamine during the treatment of depression? A systematic review of available literature

Gianmarco Ingrosso, Anthony J. Cleare, Mário F. Juruena
PubMed Summary & key facts 2025 13 citations

This systematic review looked at 16 studies of ketamine used to treat adults with depression, covering 2,174 patients. The authors found few clear cases of tolerance or dependence (four patients) and conclude that, overall, ketamine appears relatively safe for depression when given under medical supervision, with careful monitoring and dosing.…

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

Modern Psychedelic Microdosing Research on Mental Health

David F. Lo, Hasan Zia, Pranetha Rajkumar, Adarsh Thakur, Heather O’Donnell

This systematic review looked at research on psychedelic microdosing and mental health. It found 19 studies (published from 2018 onward) that reported people often said low doses of LSD or psilocybin improved mood, focus, and daily functioning, while some people reported physical discomfort or more anxiety. The authors say the…

Chemical synthesis and alkaloids Psychedelics and Drug Studies Tryptophan and brain disorders
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