Ayahuasca
The Amazonian Brew Now in the Research Spotlight
Evidence grade 2 of 5, Thin. Read how the Atlas grades evidence.
Research interest is real and growing, but the evidence is early. Observational and small studies (often among Brazilian church members or in Shipibo-framework retreats) and a body of ethnographic work suggest possible benefits for depression, anxiety, and substance dependence, and pharmacological studies indicate ayahuasca is generally physiologically tolerable in controlled settings. However, to date rigorous placebo-controlled trials are scarce, and much evidence is naturalistic, so efficacy is suggested, not established. A recurring finding is that the ritual container, set, setting, ceremony, and integration, is deeply entangled with any benefit, which is itself an important clue about how such healing works.
Reference only. Not medical advice.
What can go wrong
This is documentation, not encouragement, and it includes no preparation or dosing detail. The brew's harmala alkaloids are monoamine oxidase inhibitors, which creates dangerous interactions with many medications, especially SSRIs and other serotonergic antidepressants (risk of serotonin syndrome), and with certain high-tyramine foods. It can be hazardous for people with cardiovascular conditions and for anyone with a personal or family history of psychosis, schizophrenia, or bipolar disorder, where case reports describe precipitated mania or psychosis. Vomiting and purging are expected. Unregulated retreats vary widely in medical screening and supervision, and rare serious adverse events, including deaths reported in the context of drug combinations, have occurred. Mental health is a sensitive area: anyone considering this, particularly people with a mood, psychotic, or cardiac diagnosis, should first consult a qualified physician or mental health provider and disclose every medication and condition, because the brew is not compatible with many common prescriptions. It is illegal in most countries outside specific religious exemptions.
Ayahuasca is a bitter Amazonian brew made by combining two plants: a vine, Banisteriopsis caapi, whose harmala alkaloids inhibit monoamine oxidase, and a leaf such as Psychotria viridis that supplies DMT, which the vine's chemistry allows the body to absorb by mouth. Amazonian peoples arrived at that pairing empirically, and the brew sits at the center of Indigenous ceremony and, since the mid-20th century, of Brazilian churches such as Santo Daime and the Uniao do Vegetal. Clinical interest is real but early. A single small double-blind trial in treatment-resistant depression and a set of observational and survey studies point to possible benefit for depression and addiction, with the ceremony itself hard to separate from any effect. The safety picture is serious and includes monoamine oxidase inhibitor interactions with antidepressants and certain foods, cardiac and psychosis-spectrum risks, expected vomiting, and widely variable retreat screening. This entry is documentation, not instruction, and carries no preparation or dosing detail.
A ceremonial Amazonian plant medicine, used for millennia, now studied for depression and addiction, documented here as fact, with serious safety cautions and no how-to.
What people take it for
These are the reasons people give for taking it. They are not effects it has been shown to have.
How it is supposed to work
Ayahuasca pairs two plants: the Banisteriopsis caapi vine (rich in harmala alkaloids, which are monoamine-oxidase inhibitors) with a DMT-containing plant such as Psychotria viridis. The MAOIs prevent the gut from breaking down DMT, allowing it to act, a sophisticated pharmacological combination Amazonian peoples arrived at empirically, long before the chemistry was understood. DMT acts on serotonin (5-HT2A) receptors, producing the altered state; the harmala alkaloids add their own effects.
What people get wrong
Often saidAyahuasca is a proven cure for depression and addiction.
ActuallyThe clinical record is one small double-blind trial in treatment-resistant depression (Palhano-Fontes 2019, n=29) plus observational and survey data. It shows early signals, not established efficacy, and the trial authors call for larger randomized studies. The ceremonial setting appears difficult to separate from any benefit.
Often saidBecause it is natural and traditional, ayahuasca is safe for anyone.
ActuallyIt carries real risks. The harmala alkaloids are monoamine oxidase inhibitors, so combining the brew with SSRIs and other serotonergic drugs can trigger serotonin syndrome, and it is hazardous for people with cardiac conditions or a personal or family history of psychosis or bipolar disorder. Vomiting is expected, and retreat screening varies widely. ICEERS, a harm-reduction group, advises people with such histories to refrain.
Often saidAyahuasca is an unbroken tradition stretching back thousands of years.
ActuallyThe antiquity is genuinely contested. Archaeology confirms plant combining in the Andes about a thousand years ago, but linguistic and folkloric analysis, associated with Bernd Brabec de Mori, suggests the brew as practiced today spread across the Western Amazon only within roughly the last few centuries.
Who profits, and who pushes back
Pharmacology & psychiatry research
Suggest possible benefit for depression, anxiety, and substance dependence and general physiological tolerability in controlled settings, while noting rigorous placebo-controlled evidence remains scarce.
Amazonian Indigenous traditions
Hold ayahuasca as a sacred medicine and teacher used in ceremony for healing and insight, with the curandero, songs, and dieta integral to its use.
Ethnographers of ritual healing
Document that ayahuasca's therapeutic effects, especially for addiction, blend somatic, symbolic, and collective dimensions, with the ritual container central to healing.
Safety & interaction caution
Stresses dangerous MAOI drug and food interactions, risks for cardiac and psychosis-spectrum individuals, expected purging, and the wide variability and rare fatalities in unregulated retreats.
Where the research comes from
Most of the published research on this comes from one place. 90% of it is from Peruvian & Western Amazon. Findings that no unrelated group has reproduced are weaker than the study count makes them look.
| Place | Share of published research |
|---|---|
| Peruvian & Western Amazon | 90% |
| Brazil (churches + Indigenous) | 85% |
| Colombia & Ecuador | 70% |
| Global retreat & research settings | 55% |
How we got here
Ayahuasca is used across the Western Amazon by peoples including the Shipibo-Konibo, Ashaninka, and Tukano, and its two-plant chemistry was worked out empirically long before laboratories described it. How old the practice is remains disputed. A ritual bundle from Cueva del Chileno in southwestern Bolivia, associated with the Tiwanaku sphere and dated to roughly a thousand years ago, held plant residues including harmine and DMT, which shows early combining of psychoactive plants in the Andes. Some anthropologists and linguists, notably Bernd Brabec de Mori, argue that the brew as practiced today spread through the Western Amazon only within the last few centuries, carried along with missionary routes and the rubber trade, citing the striking similarity of ayahuasca songs and vocabulary across otherwise very different languages. In the 1930s and 1940s the brew became the sacrament of Brazilian churches, which later carried it worldwide into research, retreat tourism, and legal religious use abroad.
- c. 900-1000 CERitual bundle at Cueva del Chileno, Bolivia, holds harmine and DMT residues, evidence of early plant combining in the Andes (Miller et al. 2019)
- 17th c.Jesuit missionary accounts note psychoactive Amazonian plant brews
- 1930s-1940sSanto Daime founded around Mestre Irineu in Rio Branco, Brazil; the Uniao do Vegetal follows in the 1960s
- 1980sBrazilian authorities review and permit religious use after concluding the brew is not a recreational drug
- 2006US Supreme Court in Gonzales v. O Centro Espirita Beneficente Uniao do Vegetal unanimously allows the UDV's sacramental use under the Religious Freedom Restoration Act
- 2019Palhano-Fontes et al. publish the first double-blind randomized placebo-controlled trial of a psychedelic in treatment-resistant depression
- 2022Global Ayahuasca Survey (Bouso et al.) reports adverse-effect patterns across more than 8,000 users worldwide
How it is understood
Ayahuasca, Quechua for "vine of the soul" or "vine of the dead," is a ceremonial decoction central to many Amazonian Indigenous traditions, with the Shipibo-Konibo of the Peruvian Amazon among its most prominent stewards. It is taken at night in ceremony, led by a curandero or shaman, often with icaros (healing songs), dieta (dietary and behavioral preparation), and a communal ceremonial space (maloka). It is understood not as a recreational drug but as a medicine and teacher, used for healing, divination, and spiritual insight. In the 20th century it also became the sacrament of Brazilian syncretic churches (Santo Daime, União do Vegetal), which carried it worldwide. This entry documents the practice ethnographically and historically, it is not a how-to and contains no preparation or dosing guidance.
At a glance
- Name
- Quechua: "vine of the soul"
- Plants
- B. caapi (MAOI) + DMT plant
- Stewards
- Shipibo-Konibo & many Amazonian peoples
- Research
- Early; depression, addiction signals
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Ayahuasca. A short entry is not a safe entry.
- Cost and market. We have not documented what it sells for or who sells it.
- Supply chain. We have not mapped where it is made.
- Who uses it. We have not documented the user groups.
- What could change. No forward-looking summary yet.
- How it compares. We have not set it against the alternatives.
- Children and teenagers. We have not checked what is known about younger people.
Sources
Double-blind RCT in treatment-resistant depression, n=29, response 64 vs 27 percent at day 7; authors call for larger trials
Palhano-Fontes et al., Psychological Medicine (Cambridge University Press)
Trial abstract confirming design, arm sizes, MADRS primary outcome, journal and year
Observational addiction pilot, 12 participants, significant reductions in problematic cocaine use and improved psychological measures
Global Ayahuasca Survey adverse-effect rates across more than 8,000 users; vomiting common, medical attention rare
Systematic review linking psychotic and manic reactions to personal or family history of psychosis or bipolar disorder; screening recommended
dos Santos, Bouso, Hallak, Journal of Psychopharmacology (SAGE)
MAOI plus SSRI serotonin syndrome mechanism and contraindications; psychiatric and cardiac cautions from a harm-reduction NGO
Etymology (Quechua vine of the soul), Banisteriopsis caapi MAOI plus DMT admixture plants, contested antiquity, church founding, legal status
Thousand-year-old Bolivian ritual bundle with harmine and DMT residues; evidence of early Andean plant combining
Linguistic and folkloric evidence that modern ayahuasca practice spread within recent centuries (Brabec de Mori)
US Supreme Court unanimous ruling permitting UDV sacramental use under RFRA; DMT Schedule I; plants not internationally controlled
Justia US Supreme Court Center, Gonzales v. O Centro (546 U.S. 418)