Psilocybin, an Effective Treatment for Major Depressive Disorder in Adults – A Systematic Review

Summary & key facts

This systematic review looked at clinical studies of psilocybin for adults with major depressive disorder. It combined 6 studies with 319 participants, found that every study reported that psilocybin reduced depressive symptoms, and noted few side effects. Each study included psychological support, and the authors say more and better studies are needed to standardize session timing and support and to check for publication bias.

Key facts:

• The review included 6 studies totaling 319 participants.
• Half of the studies were randomized controlled trials and half were open‑label trials.
• Every study included psychological support as part of the treatment.
• All selected studies reported results that significantly favored psilocybin in reducing depressive symptoms.
• The studies reported few side effects associated with psilocybin.
• The authors note psilocybin’s antidepressant effects are thought to act largely through 5‑HT1a receptors.
• The review says psilocybin may have advantages over commonly prescribed SSRIs because SSRIs can carry more risks and adverse effects, but the authors call for more research before firm conclusions can be drawn.
• The paper highlights research limits: psilocybin is a Schedule I drug, there are few FDA‑approved clinical studies, and more trials are needed to reduce possible publication bias and to define treatment protocols (session timing and type of

Abstract

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.

Topics

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

Categories

Clinical Psychology Psychology Social Sciences

Tags

Adverse effect Antidepressant Anxiety Clinical psychology Clinical trial Cognition Hallucinogen Internal medicine Major depressive disorder Medicine Pharmacology Psilocybin Psychiatry Psychology