Effects of Ayahuasca on Personality: Results of Two Randomized, Placebo-Controlled Trials in Healthy Volunteers
Juliana Mendes Rocha, Giordano Novak Rossi, Flávia de Lima Osório, José Carlos Bouso, Gabriela de Oliveira Silveira, Maurı́cio Yonamine, Eduardo José Crevelin, Maria Eugênia Costa Queiroz, Jaime E. C. Hallak, Rafael G. Dos Santos
Frontiers in Psychiatry August 6, 2021 DOI: 10.3389/fpsyt.2021.688439 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Placebo-controlled Peer reviewed |
|---|---|
| Sample size | 30 |
| Population | Healthy volunteers |
| Interventions | Ayahuasca Placebo Cannabidiol |
| Duration | 21-day follow-up |
| Topics | Ayahuasca Psilocybin |
| Keywords | Placebo Hallucinogen Personality Randomized controlled trial Openness to experience Clinical psychology |
| Citations | 37 |
| Key findings | Ayahuasca produced a significant increase in Openness scores 21 days post-drug intake in only one of two trials, indicating inconsistent effects on personality. |
Abstract
Rationale: Previous studies with the serotonergic hallucinogens LSD and psilocybin showed that these drugs induced changes in personality traits, such as increases in Openness. However, results are inconsistent, and the effects of ayahuasca on personality were never investigated in a controlled trial.
Objectives: To assess the effects of ayahuasca on personality in two randomized, placebo-controlled trials in healthy volunteers.
Methods: Data from two parallel-group, randomized, placebo-controlled trials in healthy volunteers were included. In the first trial, 15 volunteers ingested ayahuasca or placebo, while in the second trial 15 volunteers received placebo+ayahuasca or cannabidiol (CBD)+ayahuasca. Personality was assessed with the NEO-Five Factor Inventory (NEO-FFI) at baseline and 21 days post-treatment.
Results: There were significant differences between groups in baseline Openness scores, but not on day 21. A significant increase in Openness scores was observed in the placebo + ayahuasca group in study 2. No other within-group differences were observed for any other domain.
Conclusions: Ayahuasca produced inconsistent effects on personality since it induced significant increase in Openness 21 days post-drug intake only in one of the trials. The absence of significant differences in the other ayahuasca groups could be due to small sample sizes and baseline differences among groups. The effects of ayahuasca and other serotonergic hallucinogens on personality should be further investigated in clinical samples.
Comparable studies
Other randomized controlled trials on ayahuasca, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomized placebo-controlled trial Patients with treatment-resistant depression | 2018 | Randomized controlled trial | n = 29 |
| Human Pharmacology of Ayahuasca: Subjective and Cardiovascular Effects, Monoamine Metabolite Excretion, and Pharmacokinetics Volunteers with prior experience in the use of psychedelics | 2003 | Double-blind placebo-controlled clinical trial | n = 18 |
| Subjective effects and tolerability of the South American psychoactive beverage Ayahuasca in healthy volunteers Healthy male volunteers with prior experience using ayahuasca | 2001 | Single-blind crossover placebo-controlled clinical trial | n = 6 |
| Increased frontal and paralimbic activation following ayahuasca, the pan-amazonian inebriant Male volunteers with prior experience in the use of psychedelics | 2006 | Randomized controlled trial | n = 15 |
| Human brain effects of DMT assessed via EEG-fMRI. Healthy volunteers | 2023 | Within-subjects, placebo-controlled design | n = 20 |
Citations in the library
Cited by 28
- Sustained effects of single doses of classical psychedelics in humans. Neuropsychopharmacology June 21, 2022
- Changes in mental health, wellbeing and personality following ayahuasca consumption: Results of a naturalistic longitudinal study. Frontiers in Pharmacology 2022
- Examining Psychedelic-Induced Changes in Social Functioning and Connectedness in a Naturalistic Online Sample Using the Five-Factor Model of Personality Frontiers in Psychology November 25, 2021
- Ayahuasca's therapeutic potential: What we know - and what not. European Neuropsychopharmacology 2023
- Ayahuasca: A review of historical, pharmacological, and therapeutic aspects. Psychiatry and Clinical Neurosciences Reports December 1, 2023
and 23 more in the library
Cites 17
- Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance Psychopharmacology July 7, 2006
- Human hallucinogen research: guidelines for safety. Journal of Psychopharmacology July 1, 2008
- Mystical experiences occasioned by the hallucinogen psilocybin lead to increases in the personality domain of openness Journal of Psychopharmacology September 28, 2011
- Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomized placebo-controlled trial Psychological Medicine June 15, 2018
- Psilocybin-occasioned mystical-type experience in combination with meditation and other spiritual practices produces enduring positive changes in psychological functioning and in trait measures of prosocial attitudes and behaviors Journal of Psychopharmacology October 11, 2017
and 12 more in the library