Ayahuasca

Plant Medicine

Ayahuasca is an Amazonian psychedelic brew that combines a DMT-containing plant with an MAO-inhibiting vine, making the DMT orally active. Used ceremonially for centuries, it produces a long, visionary, and often cathartic experience — typically including purging — lasting around 4–6 hours.

Also known as: Aya, Yagé, Yajé, Daime, Hoasca, La purga, Caapi + chacruna brew

Written by Psymerge Editorial Team · Last updated June 4, 2026

Key facts

CategoryPlant Medicine
Onset30–60 minutes
Peak1–2 hours
Total duration4–6 hours
After-effectsTiredness and a reflective afterglow into the next day

Overview

Ayahuasca is a psychoactive brew traditionally prepared in the Amazon basin by combining the vine Banisteriopsis caapi with a DMT-containing plant, most often the leaves of Psychotria viridis (chacruna). The vine contains beta-carboline alkaloids (harmine, harmaline, tetrahydroharmine) that inhibit monoamine oxidase (MAO); this prevents the body from breaking down DMT, allowing it to become active when swallowed (Domínguez-Clavé et al., 2016).

The result is a long experience — usually 4–6 hours — marked by vivid visions, deep introspection, strong emotional release, and characteristic physical purging. Used for generations in Indigenous Amazonian healing and by syncretic churches such as Santo Daime and União do Vegetal, ayahuasca has also become a focus of clinical research, with one randomized controlled trial reporting rapid antidepressant effects in treatment-resistant depression (Palhano-Fontes et al., 2019).

Because ayahuasca relies on an MAO inhibitor, it carries important drug and dietary interaction risks. This page summarises its pharmacology, effects, and risks; for more on its principal psychoactive component, see also our page on DMT.

History & origins

Ayahuasca has been prepared and used for generations by Indigenous peoples across the western Amazon, in what is now Peru, Ecuador, Colombia, Brazil, and Bolivia, within healing, divinatory, and ceremonial traditions. Western science first documented the brew and its botany in the nineteenth and twentieth centuries, and the active alkaloids of both plants were later characterised.

In the twentieth century, syncretic religions such as Santo Daime and the União do Vegetal incorporated ayahuasca as a sacrament and spread its use beyond the Amazon, in some countries securing legal protection for religious use. Since the early 2000s, scientific interest has grown rapidly, including controlled research on its antidepressant potential (Palhano-Fontes et al., 2019), alongside a global expansion of ayahuasca retreats and tourism.

Pharmacology & how it works

Ayahuasca works through a combination of two plant components. The DMT-containing plant (such as Psychotria viridis) provides DMT, a serotonergic psychedelic that acts mainly at 5-HT2A receptors. The vine Banisteriopsis caapi provides beta-carboline alkaloids (harmine, harmaline, tetrahydroharmine) that inhibit monoamine oxidase, preventing the body from breaking DMT down and so making it orally active (Domínguez-Clavé et al., 2016). The beta-carbolines also have effects of their own.

Chemical class
Plant brew (DMT plus beta-carboline MAO inhibitors)
Routes of administration
Oral (brewed tea)
Tolerance
There is no evidence of physical dependence; classic psychedelics like DMT show little acute tolerance.

Pharmacokinetics

Taken as a tea, ayahuasca comes on over 30–60 minutes, peaks at 1–2 hours, and lasts around 4–6 hours. The MAO inhibition provided by the vine is essential: without it, the DMT would be destroyed in the gut and have no effect when swallowed.

Effects

Physical Effects

  • Strong nausea, vomiting, and sometimes diarrhoea (known as 'la purga')
  • Increased heart rate and blood pressure
  • Changes in body temperature, sweating, and chills
  • Trembling or tingling
  • Dizziness

Psychological Effects

  • Vivid visions and closed-eye imagery
  • Deep introspection and review of memories and emotions
  • Strong, sometimes cathartic emotional release
  • An altered sense of time and self
  • Insight or shifts in perspective
  • Fear, anxiety, or confronting material during difficult passages

Spiritual Effects

  • Mystical and transcendent experiences
  • Feelings of connection to nature, ancestors, or the sacred
  • A sense of healing, guidance, or spiritual teaching central to ceremonial use

Dosage Information

Low: Half a cup cups of brew (oral)
Medium: About one cup cups of brew (oral)
High: More than one cup cups of brew (oral)

Ayahuasca dosing cannot be standardised: brew strength varies enormously with the plants used and the preparation, and it is traditionally measured and administered by an experienced facilitator who judges the amount for each person. Educational only and not an endorsement of use.

Risks & safety

Contraindications

Ayahuasca combines a psychedelic with an MAO inhibitor, which broadens its contraindications considerably. It is generally inadvisable for:

  • People taking serotonergic medications: SSRIs, SNRIs, other antidepressants, MAOIs, and many other drugs (see interactions below).
  • Cardiovascular conditions: heart disease or uncontrolled high blood pressure.
  • Psychiatric history: a personal or family history of psychosis, schizophrenia, or bipolar disorder.
  • Pregnancy and breastfeeding.

Drug interactions

The MAO inhibitor in ayahuasca is the source of its most serious interactions.

  • SSRIs, SNRIs, MAOIs, and other serotonergic drugs: combining these with ayahuasca can cause serotonin syndrome, a potentially life-threatening reaction. This is the single most important interaction to avoid.
  • Tyramine-rich foods and many medications: MAO inhibitors require dietary precautions and interact dangerously with numerous prescription and over-the-counter drugs, stimulants, and some supplements.
  • Stimulants: add cardiovascular strain.

This list is not exhaustive. Stop interacting medications only under medical supervision, and disclose everything you take to a clinician (Domínguez-Clavé et al., 2016).

Psychological distress & bad trips

Ayahuasca's long, intense experience can bring difficult emotions and traumatic memories to the surface. Challenging ceremonies may involve fear, panic, confusion, or distressing visions, and the physical demands of purging add to the intensity. A skilled facilitator, careful screening, and good preparation substantially reduce the risk of lasting harm, and some people may need psychological support afterwards.

Rare but serious risks

Most serious incidents with ayahuasca involve interactions, vulnerable individuals, or unsafe ceremonies rather than the brew alone:

  • Serotonin syndrome: the gravest risk, arising when the MAOI is combined with serotonergic drugs; it can be life-threatening.
  • Cardiovascular strain: raised heart rate and blood pressure can be dangerous for people with heart conditions.
  • Dehydration and exhaustion from prolonged purging.
  • Adulterated or mixed brews: adding other plants such as tobacco or Brugmansia (toé) markedly increases the danger.
  • Psychological destabilisation in vulnerable people, and rare deaths reported in retreat settings, often linked to the factors above or to negligent, unscreened ceremonies.

Vulnerable populations

Some groups face substantially higher risk and should avoid ayahuasca:

  • People taking antidepressants or other serotonergic or MAOI-interacting medications.
  • People with a personal or family history of psychosis, schizophrenia, or bipolar disorder.
  • People with heart disease or uncontrolled high blood pressure.
  • Adolescents, whose brains are still developing.
  • Pregnant or breastfeeding people.

Dependency & addiction potential

Like other classic psychedelics, ayahuasca is not considered addictive and does not produce physical dependence or compulsive use. Its risks lie in drug interactions, physical intensity, and psychological vulnerability rather than in dependence.

Overdose

Ayahuasca is not usually lethal on its own, but serious and occasionally fatal outcomes have occurred — most often through serotonin syndrome from drug interactions, pre-existing heart or psychiatric conditions, dehydration, brews adulterated with other plants, or unsafe retreat practices. If someone develops a dangerously high temperature with muscle rigidity or agitation (possible serotonin syndrome), chest pain, a very high heart rate, severe confusion, or loss of consciousness, seek emergency medical help immediately.

Harm Reduction

  • Never combine ayahuasca with SSRIs, SNRIs, other antidepressants, or serotonergic drugs — its MAOI can cause life-threatening serotonin syndrome. Stop such medication only under medical supervision.
  • Follow the dietary precautions associated with MAO inhibitors, and disclose your full health history and all medications.
  • Choose experienced, reputable facilitators who screen participants for medical and psychiatric history, and avoid retreats that do not.
  • Be very cautious of brews mixed with other plants such as tobacco or Brugmansia (toé), which add serious risks.
  • Expect purging: stay hydrated, and make sure trustworthy support is present throughout the ceremony.
  • Never participate alone or in an unsupervised setting.
  • Avoid ayahuasca if you have a heart condition or a personal or family history of psychosis or bipolar disorder.

Cultural & spiritual context

Ayahuasca sits at the heart of living Amazonian traditions, where it is regarded not as a recreational drug but as a medicine and teacher, prepared and administered by trained healers (such as curanderos, vegetalistas, or ayahuasqueros) within structured ceremonies. Different lineages and syncretic churches have their own songs (icaros), protocols, and cosmologies.

Its rapid global spread has raised significant concerns: the safety of powerful ceremonies run by undertrained or exploitative facilitators, the commercialisation and cultural appropriation of Indigenous practices, pressure on plant populations, and questions of reciprocity with the communities who hold this knowledge. Approaching ayahuasca with caution, informed consent, and cultural respect matters a great deal.

Legal Status

Laws vary widely by country and change frequently, so we don't track legal status here to avoid showing outdated information.

Check current worldwide legal status on Psychedelic Alpha

Frequently asked questions

What is in ayahuasca and how does it work?

Ayahuasca typically combines the vine Banisteriopsis caapi with a DMT-containing plant such as chacruna (Psychotria viridis). The vine's beta-carboline alkaloids inhibit the enzyme (MAO) that would otherwise destroy DMT in the gut, so the DMT becomes active when the brew is swallowed.

Why does ayahuasca make people vomit?

Nausea, vomiting, and sometimes diarrhoea are common physical effects, known as 'la purga'. In many Amazonian traditions this purging is regarded as a cleansing and meaningful part of the process rather than merely a side effect.

Is it dangerous to take ayahuasca on antidepressants?

Yes. Ayahuasca contains an MAO inhibitor, and combining an MAOI with SSRIs, SNRIs, or other serotonergic medications can cause serotonin syndrome, a potentially life-threatening reaction. Any decision to stop such medication should be made only with a clinician.

Is ayahuasca addictive?

No. Like other classic psychedelics, ayahuasca does not cause physical dependence or compulsive use. Its risks come from drug interactions, physical intensity, and psychological vulnerability rather than from addiction.

How long does an ayahuasca experience last?

Effects usually begin within 30–60 minutes, peak at around 1–2 hours, and last roughly 4–6 hours, with tiredness and a reflective afterglow often continuing into the following day. Ceremonies themselves typically run through much of a night.

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Cannabis is a widely used plant whose main active compound, THC, produces relaxation, euphoria, and altered perception by acting on the body's endocannabinoid system. It is used recreationally, medicinally, and in some spiritual contexts, and — unlike the classic psychedelics — it can lead to dependence.

Kambo

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Kambo is the dried skin secretion of the giant monkey frog (Phyllomedusa bicolor), applied to small fresh skin burns in an Amazonian purification practice. It is not a psychedelic: it triggers an intense, short-lived physical reaction — flushing, vomiting, and a racing heart — and carries real, documented risks.

Peyote

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Peyote (Lophophora williamsii) is a small, slow-growing cactus of the Chihuahuan Desert whose principal psychoactive component is mescaline. Used ceremonially for thousands of years and central to the Native American Church, it produces a long, visionary experience and is now seriously threatened by over-harvesting.

Rapé

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References & further reading

  • Palhano-Fontes, F., Barreto, D., Onias, H., et al. (2019). Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomized placebo-controlled trial. Psychological Medicine, 49(4), 655–663. https://doi.org/10.1017/S0033291718001356
  • Domínguez-Clavé, E., Soler, J., Elices, M., et al. (2016). Ayahuasca: pharmacology, neuroscience and therapeutic potential. Brain Research Bulletin, 126, 89–101. https://doi.org/10.1016/j.brainresbull.2016.03.002
  • Nichols, D. E. (2016). Psychedelics. Pharmacological Reviews, 68(2), 264–355. https://doi.org/10.1124/pr.115.011478
  • National Institute on Drug Abuse (NIDA). Psychedelic and Dissociative Drugs. https://nida.nih.gov/research-topics/psychedelic-dissociative-drugs
  • European Monitoring Centre for Drugs and Drug Addiction (EMCDDA). Drug profiles. https://www.emcdda.europa.eu/publications/drug-profiles_en
  • Erowid. Ayahuasca Vault. https://www.erowid.org/chemicals/ayahuasca/
  • DanceSafe. https://dancesafe.org/drug-information/
  • TripSit. Drug combinations chart. https://wiki.tripsit.me/wiki/Drug_combinations

About this article

Written by:
PE
Psymerge Editorial Team
Last updated June 4, 2026