Cited by 112Psychedelics and Drug StudiesPain Management and Placebo EffectReligion, Spirituality, and Psychology

The DOI matches its Crossref record; 77 of the 78 references it cites were found in a registry or an index.

A placebo-controlled study of the effects of ayahuasca, set and setting on mental health of participants in ayahuasca group retreats

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Uthaug, M. V., Mason, N. L., Toennes, S. W., Reckweg, J. T., de Sousa Fernandes Perna, E. B., Kuypers, K. P. C., van Oorsouw, K., Riba, J., Ramaekers, J. G.·2021·Psychopharmacology

Abstract

Ayahuasca is a plant concoction containing N,N-dimethyltryptamine (DMT) and certain β-carboline alkaloids from South America. Previous research in naturalistic settings has suggested that ingestion of ayahuasca can improve mental health and well-being; however, these studies were not placebo controlled and did not control for the possibility of expectation bias. This naturalistic observational study was designed to assess whether mental health changes were produced by ayahuasca or by set and setting. Assessments were made pre- and post-ayahuasca sessions in 30 experienced participants of ayahuasca retreats hosted in the Netherlands, Spain, and Germany. Participants consumed ayahuasca (N = 14) or placebo (N = 16). Analysis revealed a main effect of time on symptoms of depression, anxiety, and stress. Compared to baseline, symptoms reduced in both groups after the ceremony, independent of treatment. There was a main treatment × time interaction on implicit emotional empathy, indicating that ayahuasca increased emotional empathy to negative stimuli. The current findings suggest that improvements in mental health of participants of ayahuasca ceremonies can be driven by non-pharmacological factors that constitute a placebo response but also by pharmacological factors that are related to the use of ayahuasca. These findings stress the importance of placebo-controlled designs in psychedelic research and the need to further explore the contribution of non-pharmacological factors to the psychedelic experience.

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Crossref · 10.1007/s00213-021-05817-8

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Fig. 1 Mean ratings (SE) of stress (a) and depression (b), as assessed by DASS-21, as well as anxiety (c), as assessed by the BSI-18, and implicit arousal to negative stimuli (d), as assessed by MET. Statistical significance is indicated with an asterisk
Fig. 1 Mean ratings (SE) of stress (a) and depression (b), as assessed by DASS-21, as well as anxiety (c), as assessed by the BSI-18, and implicit arousal to negative stimuli (d), as assessed by MET. Statistical significance is indicated with an asteriskCC BY · PubMed Central
Fig. 2 Mean ratings of the experience of altered states of consciousness as assessed by the EDI and 5D-ASC (from 0 to 100%) dimensions per group (ayahuasca and placebo). Abbreviations: Ego Dissolution Inventory (EDI), oceanic boundlessness (OB), anxious ego dissolution (AED), visual restructuralization (VR), auditory alterations (AA), and reduction of vigilance (RV)
Fig. 2 Mean ratings of the experience of altered states of consciousness as assessed by the EDI and 5D-ASC (from 0 to 100%) dimensions per group (ayahuasca and placebo). Abbreviations: Ego Dissolution Inventory (EDI), oceanic boundlessness (OB), anxious ego dissolution (AED), visual restructuralization (VR), auditory alterations (AA), and reduction of vigilance (RV)CC BY · PubMed Central

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Research works printed but not linked: 3

  1. Adamson S, Metzner R (1988) The nature of the MDMA experience and its role in healing, psychotherapy and spiritual practice. ReVision 10:59–72
  2. Blewett D (1970) The psychedelics and group therapy. Aaronson, B y H Osmond
  3. Kuypers KPC, Dolder PC, Ramaekers JG, Liechti ME (2017b) Multifaceted empathy of healthy volunteers after single doses of MDMA: a pooled sample of placebo-controlled studies. J Psychopharmacol 31:589–598 · DOI · Paper page

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Authors
Uthaug, M. V., Mason, N. L., Toennes, S. W., Reckweg, J. T., de Sousa Fernandes Perna, E. B., Kuypers, K. P. C., van Oorsouw, K., Riba, J., & Ramaekers, J. G.
Affiliations
  • Maastricht University (NL)
  • Goethe University Frankfurt (DE)
Corresponding author
  • Uthaug, M. V.
  • Ramaekers, J. G.
Venue
Psychopharmacology
Published
2021-03-10
Volume
238
Issue
7
Pages
1899-1910
ISSN
  • 0033-3158 (ISSN-L)
  • 1432-2072
OpenAlex
W3133906491
Cited by
112
References
78
Citations by year
2026: 11 · 2025: 26 · 2024: 23 · 2023: 25 · 2022: 14 · 2021: 13
FWCI
12.79
Type
journal article
Language
en
Open access
Locations
  • Psychopharmacology (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Research Publications (Maastricht University) (publishedVersion, cc-by)
  • Research Publications (Maastricht University) (submittedVersion, other-oa)
Topics
  • Social Sciences › Psychology › Clinical Psychology › Psychedelics and Drug Studies
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Pain Management and Placebo Effect
  • Social Sciences › Health › Religion, Spirituality, and Psychology
Keywords
ayahuasca, set and setting, placebo response, mental health, depression, anxiety, stress, affective empathy, N,N-dimethyltryptamine
MeSH terms
Adult, Alkaloids, Mental Disorders, Ceremonial Behavior, Double-Blind Method, Female, Germany, Hallucinogens, Humans, Male, Mental Health, Middle Aged, Netherlands, Plant Extracts, Spain, Banisteriopsis

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