This survey study (n=302) explored the effects the naturalistic use of psychedelics (i.e. outside of a clinic) has on symptoms of anxiety and depression, and how various pharmacological, extrapharmacological and experience factors related to outcomes. Measurements were taken at four different time points, with reductions in depressive symptoms observed at 2 and 4 weeks. A medicinal motive, previous psychedelic use, drug dose and the type of acute psychedelic experience were all significantly associated with changes in self-rated depression (QIDS-SR-16).
“Background: Over the last two decades, a number of studies have highlighted the potential of psychedelic therapy. However, questions remain to what extend these results translate to naturalistic samples, and how contextual factors and the acute psychedelic experience relate to improvements in affective symptoms following psychedelic experiences outside labs/clinics. The present study sought to address this knowledge gap.
Aim: Here, we aimed to investigate changes in anxiety and depression scores before versus after psychedelic experiences in naturalistic contexts, and how various pharmacological, extrapharmacological and experience factors related to outcomes.
Method: Individuals who planned to undergo a psychedelic experience were enrolled in this online survey study. Depressive symptoms were assessed at baseline and 2 and 4 weeks post-psychedelic experience, with self-rated Quick Inventory of Depressive Symptomatology (QIDS-SR-16) as the primary outcome. To facilitate clinical translation, only participants with depressive symptoms at baseline were included. Sample sizes for the four time points were N = 302, N = 182, N = 155 and N = 109, respectively.
Results: Relative to baseline, reductions in depressive symptoms were observed at 2 and 4 weeks. A medicinal motive, previous psychedelic use, drug dose and the type of acute psychedelic experience (i.e. specifically, having an emotional breakthrough) were all significantly associated with changes in self-rated QIDS-SR-16.
Conclusion: These results lend support to therapeutic potential of psychedelics and highlight the influence of pharmacological and non-pharmacological factors in determining response. Mindful of a potential sample and attrition bias, further controlled and observational longitudinal studies are needed to test the replicability of these findings.
Authors: Victoria A. Nygart, Lis M. Pommerencke, Eline Haijen, Hannes Kettner, Mendel Kaelen, Erik L. Mortensen, David Nutt, Robin Carhart-Harris & David Erritzoe
Summary of Antidepressant effects of a psychedelic experience in a large prospective naturalistic sample
Since the approval of the first selective serotonin reuptake inhibitors (SSRIs) in the 1980s, major breakthroughs in the treatment of depression have been relatively sparse. However, recent population studies have found lower suicide and mental disorders rates in ‘recent’ psychedelic users.
Psychedelic therapy is generally conceived as a combination therapy, requiring both the pharmacological action of the drug and adjunctive psychological and environmental support. Contextual variables, such as set and setting, have been shown to influence both acute and subsequent longer-term outcomes linked to psychedelic use.
Researchers sought to address the knowledge gap on the effects of psychedelic therapy in naturalistic contexts by investigating changes in anxiety and depression scores before and after psychedelic experiences.
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Authors associated with this publication with profiles on BlossomMendel Kaelen
Mendel Kaelen is a neuroscientist and entrepreneur, researching and developing a new category of psychotherapeutic tools for care-seekers and care-providers. Mendel has researched the incomparable effects of music on the brain during LSD-assisted psychotherapy. His work has determined how LSD increases enhanced eyes-closed visual imagery, including imagery of an autobiographical nature. This gives light to how music can be used as another dimension in helping psychotherapists create the ideal setting for their patients.
David John Nutt is a great advocate for looking at drugs and their harm objectively and scientifically. This got him dismissed as ACMD (Advisory Council on the Misuse of Drugs) chairman.
Dr. Robin Carhart-Harris is the Founding Director of the Neuroscape Psychedelics Division at UCSF. Previously he led the Psychedelic group at Imperial College London.
David Erritzoe is the clinical director of the Centre for Psychedelic Research at Imperial College London. His work focuses on brain imaging (PET/(f)MRI).
Institutes associated with this publicationImperial College London
The Centre for Psychedelic Research studies the action (in the brain) and clinical use of psychedelics, with a focus on depression.
University of Copenhagen
The Neurobiology Research Unit (NRU) at Copenhagen University Hospital have been carrying clinical and preclinical research with psychedelics since 2017.