Ayahuasca Safety, Contraindications & How to Prepare

Written By Gaian Rhythm

Last updated: May 2026 | Reading time: ~18 minutes

Most of the writing about ayahuasca safety falls into one of two camps. There's the kind that buries the risks in reassuring language because the person writing it wants you to book a retreat. And there's the kind that leads with horror stories and worst-case scenarios because fear gets clicks.

This is neither of those.

We've been facilitating ayahuasca ceremonies for years. We've seen what happens when people come to this work well-prepared and genuinely screened. We've also seen, and heard from others in the field, what happens when they don't. The difference is not subtle.

This guide covers what you actually need to know: which medical situations create genuine risk, which medications interact dangerously, what the dieta is and why it matters, and how to prepare yourself physically, mentally, and logistically for a safe and meaningful experience. Read it carefully. Share it with your doctor if you're navigating the medication piece. And if something in here gives you pause, sit with that rather than looking for a way around it.

The Honest Starting Point: Ayahuasca Is Generally Safe, With Important Exceptions

A 2024 systematic review published in the Journal of Psychoactive Drugs analyzed adverse events and toxicity data across preclinical, clinical, and epidemiological studies. The conclusion was that ayahuasca is generally safe when used in appropriate ceremonial or clinical settings with proper screening. Serious adverse events were most commonly associated with pre-existing psychiatric conditions, concomitant use of contraindicated medications, or recreational use outside any ceremonial container.

That finding matters. It means the risk profile of ayahuasca is not fixed. It depends heavily on who is sitting, what they're taking, and how carefully the retreat center has screened and prepared them.

The goal of this article is to help you understand exactly which factors create risk, so you can honestly assess where you stand.

Medication Contraindications: The Most Critical Safety Category

The number one cause of medical emergencies during ayahuasca retreats is combining the brew with prescription drugs. This is not a fringe concern. It is the most common and most preventable serious risk in the entire field.

Here is why. Ayahuasca contains beta-carboline compounds, primarily harmine, harmaline, and tetrahydroharmine, that act as monoamine oxidase inhibitors, or MAOIs. MAOIs affect how your body processes serotonin and other neurotransmitters. Certain medications work on the same system. When you combine them, the results can be severe.

SSRIs and SNRIs

Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are among the most commonly prescribed medications in the world. They include drugs like fluoxetine (Prozac), sertraline (Zoloft), escitalopram (Lexapro), paroxetine (Paxil), venlafaxine (Effexor), and duloxetine (Cymbalta).

Combining ayahuasca with SSRIs can cause serotonin syndrome, a dangerous and potentially life-threatening condition. Serotonin syndrome occurs when there is too much serotonin activity in the nervous system. Symptoms range from headache, agitation, and rapid heartbeat at the mild end to muscle rigidity, high fever, seizures, and organ failure in severe cases.

The timeline varies depending on how you're taking the medication. If you take an SSRI daily, you'll need to taper off under medical supervision and then allow at least 2 weeks of abstinence after your last dose before ceremony. Fluoxetine (Prozac) is the exception: because of its unusually long half-life, it requires a longer clearance period after the taper ends, typically around 4 weeks of abstinence after stopping. If you take an SSRI occasionally or as-needed rather than daily, the taper may not be necessary at all, but the 2-week abstinence window before ceremony still applies. Every situation is different. Bring your full medication history to your prescribing doctor and to your retreat center's intake process, and build your plan from there.

Two additional things worth knowing: SSRIs don't just create a safety risk, they also significantly blunt or completely block the effects of ayahuasca. People who come to ceremony still on SSRIs often experience very little, which is both a wasted opportunity and a sign that the body isn't clear. And after ceremony, restarting SSRIs should be avoided for at least 2 weeks to allow the body to rebalance.

Never stop an SSRI abruptly. Discontinuation syndrome is real and can be serious. Work with your prescribing doctor to create a tapering plan well in advance of your intended retreat date.

Pharmaceutical MAOIs

Prescription MAO inhibitors, including phenelzine (Nardil), tranylcypromine (Parnate), isocarboxazid (Marplan), and selegiline (Emsam), should never be combined with ayahuasca. The combination of pharmaceutical MAOIs with the natural MAOIs in ayahuasca dramatically amplifies the effect and can cause hypertensive crisis, a sudden and dangerous spike in blood pressure. Pharmaceutical MAOIs should be discontinued at least 2 weeks before ceremony, under medical supervision.

Tricyclic Antidepressants

Older antidepressants including amitriptyline (Elavil), imipramine (Tofranil), and nortriptyline (Pamelor) also interact with the serotonin system and are contraindicated with ayahuasca. As with SSRIs, a medically supervised taper followed by at least 2 weeks of abstinence is the standard approach. Work with your doctor on the specifics.

Other Psychiatric Medications

Benzodiazepines such as Xanax and Klonopin can dull the experience or cause seizures when withdrawn too abruptly. Antipsychotics including risperidone, quetiapine (Seroquel), and aripiprazole (Abilify) are also contraindicated. If you are taking any psychiatric medication not listed here, disclose it to your retreat center and consult your doctor. This list is not exhaustive.

ADHD Medications

Stimulant medications including methylphenidate (Ritalin) and amphetamine-based medications like Adderall should be discontinued before ceremony. These affect dopamine and norepinephrine pathways that interact with ayahuasca's MAOI activity.

Blood Pressure Medications

Certain antihypertensive medications interact with MAOIs in ways that can cause unpredictable blood pressure changes during ceremony. If you are managing hypertension with medication, discuss this explicitly with both your doctor and your retreat center before proceeding.

St. John's Wort

This is the one that surprises people most. St. John's Wort is an herbal supplement, widely considered mild and natural, but it has meaningful effects on the serotonin system. St. John's Wort must not be taken within 2 weeks of working with ayahuasca. If you are using it regularly, disclose this during screening.

Recreational Substances

Cocaine, MDMA, amphetamines, and other stimulants should be avoided in the weeks leading up to ceremony. Cannabis is worth mentioning separately: while not dangerous in the way stimulants are, it is generally understood in the Shipibo tradition we work within to interfere with the medicine's clarity and effectiveness. We ask participants to abstain for at least two weeks before ceremony.

Psychiatric and Medical Contraindications

Psychosis and Schizophrenia

A personal history of psychosis, schizophrenia, or bipolar disorder with psychotic features is the most significant psychiatric contraindication. If you yourself have experienced psychotic episodes, a break from reality, or severe paranoia, this is something that needs to be disclosed and carefully evaluated before you sit in ceremony. Ayahuasca can trigger or worsen psychotic episodes in people with this vulnerability, even if they have been stable for a long period.

Family history is a different matter. Having a parent or sibling with schizophrenia or bipolar disorder does not disqualify you. It is useful information for your facilitator to have, and worth disclosing during intake, but it is not a barrier to ceremony on its own.

This is not a guideline we bend on the personal history piece. If that applies to you, please disclose it. An honest conversation with a qualified facilitator is not a guaranteed no, but it requires full information to be navigated responsibly.

Cardiovascular Conditions

Ayahuasca increases heart rate and blood pressure during the experience. For most healthy people this is not a concern. For people with a history of heart disease, arrhythmia, or poorly controlled hypertension, this cardiovascular activation creates real risk. If you have any significant cardiac history, get medical clearance from your cardiologist before attending a retreat, and make sure the retreat center is aware.

Liver Disease

The beta-carbolines in ayahuasca are processed by the liver. Significant liver disease is a contraindication because impaired liver function can affect how the body processes the medicine, potentially leading to unpredictable and prolonged effects.

What a Responsible Retreat Center Should Ask You

Before accepting your application, any reputable retreat center should conduct a thorough medical and psychological intake. At Gaian Rhythm, this is not a formality. It is where we determine whether someone is safe to work with the medicine and what additional support they may need.

A proper intake should cover:

  • Full medication list, including supplements and herbal medicines

  • Psychiatric history, including any family history of psychosis

  • Cardiovascular history

  • History of seizures

  • History of liver disease

  • Current mental health status

  • Trauma history

  • Substance use history

  • Pregnancy status

If a retreat center accepts your deposit without asking these questions, that is a significant red flag. We cover this in depth in [Red Flags: How to Spot an Unsafe Ayahuasca Retreat].

The Dieta: What It Is and Why It Actually Matters

The word "dieta" gets used loosely in Western ayahuasca culture, often to mean a list of foods to avoid before ceremony. In the Shipibo tradition we work within, it is considerably more than that.

The traditional dieta is a period of restriction and refinement, physical, dietary, behavioral, and relational, that prepares the body and the spirit for the work of ceremony. Master plants may be dieted over weeks or months as part of a healer's training. For retreat participants, we work with a modified version that focuses on the most important elements.

The Dietary Guidelines

Foods to avoid in the week before ceremony:

The primary dietary concern with ayahuasca is tyramine, an amino acid found in aged, fermented, and preserved foods. Because ayahuasca is an MAOI, consuming high-tyramine foods before ceremony can cause hypertensive reactions. Foods to avoid include:

  • Aged cheeses (fresh cheeses like mozzarella and ricotta are generally fine)

  • Cured, smoked, or fermented meats including salami, pepperoni, and aged deli meats

  • Fermented foods including sauerkraut, kimchi, miso, soy sauce, and tempeh

  • Overripe or dried fruit

  • Tap beer and red wine (all alcohol should ideally be avoided for at least a week)

  • Yeast extracts including Marmite and Vegemite

Foods worth reducing or avoiding:

Pork, red meat, and heavily processed foods are traditionally restricted in the dieta not because of tyramine risk but because they are considered energetically heavy in ways that affect how the medicine works. This is not a claim we can footnote with a clinical trial. It is the teaching of the tradition. We've seen enough ceremony to take it seriously.

What to eat:

Fresh vegetables, fruits, whole grains, legumes, eggs, fish, and chicken are all appropriate. Simple, clean, lightly seasoned food is the general principle. Your body is being prepared to receive something powerful. Treating it accordingly makes sense.

Salt and sugar:

The traditional dieta reduces salt and sugar significantly. This is not about tyramine. It's about reducing sensory stimulation and making the body more receptive. We recommend reducing but don't require elimination.

Alcohol and Recreational Substances

Alcohol should be avoided for at least a week before ceremony, ideally two weeks. This is both a safety and an energetic consideration. Cannabis, as mentioned above, at least two weeks. Other recreational substances as long as possible before arrival.

Sexual Activity

Traditional dieta guidelines include abstaining from sexual activity in the days before ceremony. This is taken seriously in the Shipibo tradition and we pass that guidance along to participants. The underlying understanding is that sexual energy is closely related to creative and spiritual energy, and the dieta asks you to conserve and redirect it.

Media, Stress, and Mental Preparation

The dieta is also about what you consume mentally and emotionally. The week before ceremony is not the time for intense news consumption, conflict-heavy conversations, horror films, or anything that deliberately agitates the nervous system. This is not about avoidance. It's about arriving in ceremony with as clear a field as possible.

Preparation Beyond the Dieta

Set Your Intention

Some people arrive with a clear intention, a specific question they're carrying, something they want to understand, release, face, or open to. Others simply feel called without knowing exactly why, and that's completely fine too. The medicine doesn't require you to have it figured out before you arrive.

If an intention does come to you naturally, write it down. Revisit it the morning of ceremony. Hold it lightly rather than as a demand. And if nothing comes, trust that. Showing up open is its own kind of readiness.

Do Your Research

Know the lineage your facilitators work in. Know who your healer is and what their training involved. Know what the ceremony structure looks like, how many ceremonies are included, what the days in between look like, what integration support is provided and by whom. We've already said this in [What Is Ayahuasca? A Complete Guide] and we'll say it again here: ask the center how they relate to the tradition they draw from. That question alone tells you a lot.

Tell Someone

Make sure someone you trust knows where you're going, how long you'll be there, and has contact information for the center. It's worth making explicit for something this significant.

Prepare for Integration

Integration is what happens after you come home. It's the process of making sense of what arose in ceremony and actually bringing it into your life in a way that creates lasting change. Without it, even the most powerful experience can fade into memory or, worse, leave you destabilized without the tools to find your footing again. It is not an optional add-on. It is where a significant portion of the real work happens.

When evaluating any retreat center, ask specifically who leads their integration support and what that person's qualifications are. There is a wide range of what passes as "integration support" in this field, from genuinely skilled, trained practitioners to people whose primary credential is having drunk ayahuasca many times. Those are not the same thing, and the difference matters.

At Gaian Rhythm, our integration offerings are led by Kate, who holds a master's degree in counseling and a professional background in the mental health field. Her work is informed by Internal Family Systems, parts work, somatic awareness, and compassionate self-inquiry. Within Gaian Rhythm, Kate serves as an integration specialist and group facilitator, supporting participants through reflection, meaning-making, and grounded integration after ceremony. Her role in this setting is not as a therapist and does not constitute psychotherapy, diagnosis, or mental health treatment.

Our support also doesn't end when the retreat does. We host weekly integration calls open to anyone who has ever sat with us, and every retreat group has an ongoing online community where participants stay connected with each other and with our team. If you don't have a strong support system at home, that's not a barrier. We've built one you can lean on. Read more in [Ayahuasca Integration: How to Make the Most of Your Experience].

Physically Prepare

Get enough sleep in the week before ceremony. Eat well. Move your body. Arrive in a reasonably rested state. You're going to ask a lot of your nervous system. Give it the best possible starting conditions.

What Happens If Something Goes Wrong in Ceremony?

Any reputable retreat center should have clear protocols for managing medical and psychological difficulty during ceremony.

Questions worth asking before you book:

  • Does at least one member of the facilitation team have first aid, CPR, or first responder training?

  • What is the facilitator-to-participant ratio?

  • How have you handled medical emergencies in the past?

  • What is your protocol if someone is in psychological distress?

If a center can't answer these questions clearly, keep looking.

Frequently Asked Questions

I take antidepressants. Can I still attend a retreat? Possibly, and the path forward depends on your specific medication and how you're taking it. If you take an SSRI daily, you'll need a medically supervised taper followed by at least 2 weeks of abstinence before ceremony. Fluoxetine (Prozac) needs a longer clearance period after tapering, around 4 weeks, due to its long half-life. If you take something occasionally or as-needed rather than daily, you may not need a taper at all, but the 2-week abstinence window still applies. Some people also take medications that don't require tapering at all, just cessation. Bring your full medication history to your prescribing doctor first, then to your retreat center's intake process. Do not stop any medication abruptly without medical guidance.

I smoked cannabis last week. Is that a problem? Cannabis is not dangerous in combination with ayahuasca the way SSRIs or stimulants are. But it is understood in many traditions to interfere with the clarity and depth of the experience. We ask participants to stop at least two weeks before retreat. The further out the better.

I have a history of anxiety and depression but I'm not on medication. Is that a concern? A history of anxiety and depression is not a contraindication. Many people come to this work specifically because of these conditions, and the research on ayahuasca's antidepressant effects is strongest in exactly this population. What matters is that you're honest with your facilitators about where you are currently, that you're not in acute crisis, and that you have support in place for integration.

What if I have a difficult experience in ceremony? Difficult experiences are common and are not the same as dangerous ones. A skilled healer works with what arises, including difficulty. The quality of the container matters enormously here. Before you book, understand what happens when someone is struggling. A center with experienced facilitators, good participant ratios, and a healer who has navigated this many times is very different from one that hasn't thought this through.

How do I know if a retreat center is actually safe? Read [Red Flags: How to Spot an Unsafe Ayahuasca Retreat] for a thorough breakdown of what to look for and what to avoid.

A Final Word

Safety and sacredness are not in tension. The most carefully screened, best-supported ceremonies are also, in our experience, the most meaningful ones. When people arrive prepared, medically cleared, and held in a strong container, the medicine has the best possible conditions to do its work.

We screen every participant thoroughly because we care about what happens to them, not as a liability exercise. The questions we ask in intake are the same questions in this article. If your answers raise flags, we'll tell you honestly rather than take your money and hope for the best.

If you're ready to take the next step, read [What Is the Ayahuasca Dieta and Why Does It Matter?] for a deeper look at the traditional preparation, or [Red Flags: How to Spot an Unsafe Ayahuasca Retreat] to make sure you know what you're evaluating when you research centers.

This article is educational in nature and does not constitute medical advice. If you are considering ayahuasca and are currently taking any medications or managing a health condition, please consult a qualified medical professional before proceeding.

Sources

Gaian Rhythm
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