How to choose an ayahuasca retreat

What ayahuasca is

Ayahuasca is a brew made by long boiling of the Banisteriopsis caapi vine, usually combined with Psychotria viridis leaves, known as chacruna, or with Diplopterys cabrerana. The leaves contain DMT, a psychedelic that the gut and liver normally break down when it is swallowed. The vine contains harmine, harmaline and tetrahydroharmine, which reversibly block the enzyme responsible, monoamine oxidase A (MAO-A), so the DMT reaches the brain.

Indigenous peoples of the north-western Amazon, in today’s Brazil, Peru, Colombia and Ecuador, have used it for centuries, and mestizo communities use it too. Among the Shipibo-Konibo-Xetebo, about 32,000 people living mainly in Peru’s Ucayali region, healers called onaya, and the most accomplished, meraya, drink the brew with the patient at night and sing songs called íkaros as part of the healing. They learn these songs during a long period of dieta. In 2016 Peru declared the Shipibo íkaros part of its national cultural heritage.

Syncretic Brazilian churches founded between the 1930s and the 1960s, the best known being Santo Daime, Barquinha and the União do Vegetal (UDV), drink it as a sacrament and have since spread to Europe, the United States and beyond. ICEERS, a harm-reduction foundation, counted at least 232 retreat centres in 2019, 173 of them in Peru and 20 in Costa Rica.

Medical risks and who should not drink

Vomiting and diarrhoea, which ceremonies call the purge, are expected effects. In a large online survey of 10,836 people from more than 50 countries, 69.9 per cent reported acute physical effects, mostly vomiting, and 2.3 per cent later needed medical attention. More than half reported difficult mental or emotional effects in the following weeks or months; most saw these as part of a positive process, but about one in eight sought professional help.

In studies of healthy volunteers, a dose raised blood pressure and heart rate moderately and briefly, with diastolic pressure up by about 10 mmHg. Its effects in older people and in people with high blood pressure or heart disease are unknown. ICEERS guidance advises against it for anyone with cardiovascular problems, serious hypertension, epilepsy, recent surgery or fractures, or an acute infection. A personal or family history of psychosis, or of mania as in bipolar disorder, is the clearest psychiatric reason to stay away: reviews advise against use, and a switch into mania after a ceremony has been reported. There are no safety data for pregnancy, and high-dose animal studies found harm to unborn young.

Because of the MAO-A block, ayahuasca taken with drugs that raise serotonin may cause serotonin syndrome. Its first signs, such as confusion and nausea, resemble the brew’s ordinary effects, and it can progress to tremor, seizures, loss of consciousness and death. A 2024 systematic review found no confirmed case caused by ayahuasca, so the size of the risk is uncertain, not zero. A pharmacology review advises avoiding SSRI and SNRI antidepressants, tricyclics, trazodone and St John’s wort, and flags lithium, methadone, dextromethorphan, triptans, levodopa, metoclopramide, linezolid, phentermine and pseudoephedrine as serotonergic too. It calls MDMA, LSD, psilocybin, mescaline and 5-MeO-DMT high-risk combinations, with deaths reported. Changing a prescribed medicine is a decision for the prescriber, planned well before travel.

What good screening and care look like

The ICEERS good practice guide sets a practical standard. Before accepting anyone, a centre sends health and mental-health questionnaires, holds a one-to-one interview, and declines applicants it has doubts about. It knows what is in its brew and how strong it is, and when unsure it gives less. During a ceremony there are enough helpers, nobody is ever left alone, and people sit up rather than lie down so that vomiting cannot cause choking. The team has first-aid knowledge and an emergency plan that every member knows, someone qualified to prescribe medicine is available, and the venue is not too isolated. Before anyone leaves, staff check each person, stay reachable afterwards, and refer people to professionals when their own support falls short.

Brazil’s church rules require an interview with newcomers so that the brew is not given to people with a history of mental disorder or to anyone under the influence of alcohol or other drugs, and they ask participants to stay until the effects have worn off. Researchers suspect that some tourists with health problems reach ceremonies without any screening.

Questions to ask a centre

ICEERS asks for enough helpers without fixing a ratio, so concrete answers matter:

• Healers: who leads the ceremonies, which community they come from, who trained them and for how long, and whether that community recognises them.
• The brew: every ingredient, any use of toé (Brugmansia) or tobacco, and how doses are decided.
• Numbers: how many people drink in each ceremony and how many trained helpers stay in the room all night.
• Screening: which forms are used, who reads them, and what gets someone turned away.
• Emergencies: the nearest hospital and travel time at night, who on staff has medical training, and which medicines are on site.
• Other substances: any tobacco purges, 5-MeO-DMT or other preparations offered alongside ayahuasca.
• Aftercare: what support continues after departure, and for how long.
• Reciprocity: who owns the centre, how healers are paid, what goes back to their communities, and where the plants come from, cultivated or wild.

On plants, Brazil’s 2010 rules ask each church to grow its own vine and leaf rather than deplete wild stands.

Warning signs: abuse and deaths

Guidance published in 2018 by the Chacruna Institute, written with survivors, healers and researchers, documents sexual abuse by healers and facilitators ranging from invasive touching to rape; time alone with a healer is a common setting. Healing practices such as sopladas, in which tobacco smoke is blown over the body, limpiezas and plant baths never require touching intimate parts or undressing fully. Its warning signs include remarks about a person’s looks, a lot of touching, requests for secrecy, offers of love magic, claims that someone is special or chosen, and offers of other psychoactive substances. It warns that sex with a healer can be an abuse of power even when it looks consensual, and advises going with a trusted companion and checking a healer’s reputation with past participants, especially women.

A 2023 ICEERS review of media reports counted 58 deaths linked to ayahuasca between 1994 and 2022. No forensic examination has shown the basic vine-and-leaf brew causing fatal poisoning, but 16 people died soon after drinking without any autopsy. Established causes point to specific precautions: tobacco poisoning (4 deaths), scopolamine poisoning, traced in the confirmed case to Brugmansia (1 confirmed, 2 possible), probable poisoning by synthetic 5-MeO-DMT (1), drinking too much water (1), drowning (3) and heart attacks (2, at least one in a person with a serious heart condition). The list also includes 14 suicides and 8 homicides, and not everyone on it had drunk ayahuasca in the hours before death. All 17 deaths recorded in Peru were linked to retreat centres. In Colombia in 2011, two men died on one night after a rural ceremony attended by more than 150 people.

In short, the red flags are no health questionnaire, vague answers, extra plants or substances, large groups with few helpers, no emergency plan, private sessions with a healer, secrecy and promised cures.

The law, country by country

The position below was checked on 1 October 2026. DMT is controlled under international drug treaties, but the International Narcotics Control Board has said that neither the brew nor its plants are under international control, so national law decides.

Peru: in 2008 the National Institute of Culture, by Resolution 836/INC, declared the traditional knowledge and uses of ayahuasca by native Amazonian communities part of the national cultural heritage. The resolution expressly sets these apart from decontextualised, commercial Western use. It is a heritage measure, not a licensing system for retreats.

Colombia: no law specifically permits or prohibits yagé, as the brew is called there, but the state gives it cultural recognition and has never banned it. Travelling healers called taitas have led ceremonies in Colombian cities since the 1970s.

Costa Rica: in January 2025 the Ministry of Health warned that DMT, the brew’s main active compound, is a controlled substance and that any ayahuasca product must comply with national control and registration rules. It called ceremonies that promise healing an unauthorised practice, noted that such ceremonies were being held around the country, and advised people not to take part.

Brazil: Resolution 1 of the National Drug Policy Council (CONAD), of 25 January 2010, recognises religious use and confines it to religious rituals. It treats sale, tourist packages, use with illegal drugs and unproven therapeutic use as improper, so commercial retreats fall outside it.

Netherlands: DMT is on List I of the Opium Act. Lower courts had several times accepted a Santo Daime church’s religious-freedom defence. On 1 October 2019, however, the Supreme Court upheld the conviction of a church member who had imported just over 33 kilograms of the brew in 2015. It held that the import ban protects public health and justifies limiting religious freedom.

Elsewhere in Europe, France classifies ayahuasca as a narcotic; in other countries, because the brew contains DMT, authorities and courts have read the law in different ways.