Psilocybin, an Effective Treatment for Major Depressive Disorder in Adults - A Systematic Review
Tessa Watford, Naqash Masood
School of Life Sciences, Keele University, Staffordshire, UK
Correspondence to: Tessa Watford
School of Life Sciences, Keele University, ST5 5BG, Staffordshire, UK
Received: August 2, 2023; Revised: August 18, 2023; Accepted: October 16, 2023; Published online: October 16, 2023.
© The Korean College of Neuropsychopharmacology. All rights reserved.

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Psilocybin is a classical psychedelic which has been utilised for healing purposes for millenia. However, with its classification as a Schedule I substance, research into this compound is scarce with few FDA-approved clinical studies. Despite this, profound findings into its antidepressant effects (largely through its action on 5-HT1a receptors) in mental illnesses such as major depressive disorder have rapidly increased interest back into their potential therapeutic benefits. This systematic review provides an analysis of the studies examining the clinical use of psilocybin for major depressive disorder. In total 6 studies were selected, including 319 participants, with half being randomised controlled trials and half open label trials. In every study psychological support was included as an integral part of the treatment. It was found that every study significantly favoured the use of psilocybin in reducing depressive symptoms, with few side effects. This gives psilocybin an advantage over commonly prescribed selective serotonin reuptake inhibitors (SSRIs), which carry more risk and cause more adverse effects. This drug therefore shows promise for being used as a clinical treatment for major depressive disorder, however future research should develop a paradigm for its use, with the timing of sessions and type of psychological support specified to allow for more precise analysis of the clinical effects of the drug. Additionally, more studies into its clinical efficacy are needed for appropriate detection of any publication bias. With this, psilocybin could prove to be revolutionary in treating depression and become an alternative medication to SSRIs.
Keywords: Psilocybin; Depression

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