Ayahuasca Contraindications: The Full List of Medications and Substances
Updated: Oct 14
Short answer. Ayahuasca creates three separate interaction risks: serotonin overload from MAO-A inhibition, hypertensive crisis from unmetabolised tyramine and stimulants, and increased cardiac and seizure load. The highest-risk substances are SSRIs, SNRIs, tricyclics, MAOIs, tramadol, triptans, dextromethorphan, St John's wort, 5-HTP and MDMA. Lithium is an absolute contraindication. Holistika Center screens every participant against this list on a 1:1 call before confirming a place.
Most retreat guidance covers antidepressants and stops there. That leaves out the categories where people actually get caught — the migraine tablet, the cold remedy, the supplement that does not feel like a drug.
This is the full picture, organised by why each item is a problem. Read the reasoning rather than only the list, because the reasoning lets you assess something that is not named here.
Read this first. Educational content, not medical advice. Never stop a prescribed medication without your prescriber's supervision. Disclose everything during screening — including anything you take occasionally.
Why are there three separate risks, not one?
Different substances trip different mechanisms, and understanding which one applies tells you how serious a given interaction is.
Risk 1 — serotonin overload
Harmala alkaloids in the Banisteriopsis caapi vine — harmine, harmaline and tetrahydroharmine — inhibit monoamine oxidase A, the enzyme that clears serotonin. Anything else that raises serotonin can push the system into serotonin syndrome: agitation, tremor, rigidity, rapid heart rate, hyperthermia, and in severe cases seizures and cardiovascular collapse.
Risk 2 — hypertensive crisis
MAO inhibition also means tyramine and sympathomimetic compounds are not broken down normally. Accumulating tyramine can trigger a sudden, dangerous rise in blood pressure — severe headache, palpitations, nausea. This is the same mechanism behind the dietary restrictions given to patients on psychiatric MAOIs, and it is the reason the ayahuasca dieta exists.
Risk 3 — cardiac and seizure load
Ayahuasca reliably raises heart rate and blood pressure. Some substances additionally lower the seizure threshold. Combined with a long night, dehydration and vomiting, the physiological load is real.
Category 1 — Serotonergic substances (highest risk)
Everything here raises serotonin. Combined with MAO inhibition, this is the serotonin syndrome group and the one that causes fatalities.
Type | Examples |
SSRIs | Fluoxetine, sertraline, paroxetine, citalopram, escitalopram, fluvoxamine |
SNRIs | Venlafaxine, duloxetine, desvenlafaxine |
Tricyclics | Amitriptyline, clomipramine, nortriptyline, imipramine |
MAOIs | Phenelzine, tranylcypromine, moclobemide, selegiline |
Other antidepressants | Mirtazapine, trazodone, vortioxetine |
Migraine medication | Sumatriptan and other triptans |
Painkillers | Tramadol, pethidine, fentanyl |
Cough medicine | Dextromethorphan — labelled DM, DXM or Tuss |
Herbal and OTC | St John's wort, 5-HTP, L-tryptophan, SAM-e |
Recreational | MDMA, cocaine, amphetamines, prescribed ADHD stimulants |
Discontinuation timelines depend on half-life and on a safe taper, and the two are frequently confused. See our full breakdown of ayahuasca and antidepressants for how to work yours out with your prescriber.
Category 2 — Blood pressure risk
Because MAO inhibition prevents normal breakdown of tyramine and sympathomimetics, these can produce a hypertensive crisis.
Medications and supplements
Decongestants — pseudoephedrine, phenylephrine, ephedrine. Present in most cold and flu remedies.
Appetite suppressants and thermogenic weight-loss supplements
Antihypertensives — not because they raise pressure, but because interaction with a brew that does is unpredictable. Requires medical review rather than automatic exclusion.
High-dose caffeine and pre-workout formulas
Tyramine-rich foods — why the dieta exists
This is a safety rule, not a spiritual discipline. Avoid for at least two weeks before ceremony:
Aged and hard cheeses
Cured, smoked and processed meats — salami, bacon, smoked fish
Fermented foods — sauerkraut, kimchi, miso, soy sauce, tempeh
Overripe or dried fruit
Broad beans and fava beans
Yeast extracts — Marmite, Vegemite
Draught beer and red wine
Category 3 — Cardiac, seizure and CNS risk
Lithium. The one we treat as absolute. Credible reports link lithium combined with serotonergic psychedelics to seizures and other serious adverse events. This is not a timeline question — Holistika Center does not accept participants taking lithium.
Bupropion. Lowers the seizure threshold; contraindicated with MAO inhibition.
Antipsychotics. Usually accompany a diagnosis that is itself contraindicated.
Benzodiazepines and sleeping medication. CNS depressants, and they blunt the experience considerably.
Opioids. Respiratory depression, and several are serotonergic in addition.
Anti-seizure medication. Requires specialist advice. Never stop epilepsy medication in order to attend a ceremony.
Category 4 — Recreational substances
Substance | Minimum before ceremony | Why |
Alcohol | 2 weeks; longer for heavy use | Liver load, dehydration, blunted experience |
Cannabis | 2–4 weeks | Most under-declared substance in this field. Daily users consistently report harder ceremonies. |
MDMA | 6+ weeks | Strongly serotonergic; serotonin syndrome risk |
Cocaine, amphetamines | 2–4 weeks | Cardiovascular load and serotonergic activity |
Kratom, kava | 2 weeks | Both active on relevant systems, both routinely forgotten |
Nicotine | Not contraindicated | Mapacho is traditional; vaping and cigarettes are worth reducing |
Medical conditions that exclude or require clearance
Absolute contraindications | Requires medical clearance |
Schizophrenia or psychotic disorder — personal or first-degree family history | Controlled hypertension |
Bipolar I disorder | Type 1 or type 2 diabetes |
Serious heart conditions, arrhythmia, recent cardiac event | Liver or kidney impairment |
Pregnancy and breastfeeding | Thyroid conditions |
Epilepsy | Previous stroke |
Active suicidality | Active or recent eating disorder |
Recent psychiatric hospitalisation | Glaucoma |
Family history matters more than people expect. A parent or sibling with a psychotic disorder is a genuine risk factor even if you have never had symptoms, because vulnerability to psychosis is substantially heritable. This is covered in more detail in our article on who ayahuasca is not for.
The three that catch people out
If you remember nothing else from this page:
1. Cold and flu remedies. They contain decongestants and frequently dextromethorphan. People take one for a blocked nose on the morning of ceremony without a second thought.
2. Migraine medication. Triptans are serotonergic. Almost nobody thinks of them as psychiatric drugs, and almost nobody declares them.
3. Supplements. St John's wort and 5-HTP are sold in supermarkets next to the vitamins, and are pharmacologically serious in this context.
What to bring to your screening call
Bring the packets, not your memory of them. Specifically:
Every prescribed medication, with dose and how long you have taken it
Anything taken occasionally rather than daily — painkillers, sleep aids, antihistamines
All supplements, including anything herbal or "natural"
An honest account of recreational substance use, including cannabis
Your psychiatric history and known family psychiatric history
Any cardiac, neurological, liver or kidney diagnosis
Screening only protects you if what it is screening is accurate. A retreat centre cannot catch what you do not tell it.
Frequently asked questions
What medications cannot be taken with ayahuasca?
SSRIs, SNRIs, tricyclic antidepressants, MAOIs, lithium, tramadol, triptans, dextromethorphan, St John's wort, 5-HTP and stimulants including MDMA and prescribed ADHD medication. Decongestants and antihypertensives also require review because of hypertensive risk.
Why can't you eat cheese before ayahuasca?
Because ayahuasca inhibits monoamine oxidase, the enzyme that breaks down tyramine. Aged cheese is high in tyramine, and unmetabolised tyramine can cause a hypertensive crisis — a sudden dangerous rise in blood pressure.
Can I take ayahuasca if I smoke cannabis?
Cannabis is not a direct pharmacological contraindication, but daily users consistently report more difficult ceremonies. Two to four weeks abstinence is a reasonable minimum, and it should be declared during screening rather than omitted.
Is lithium safe with ayahuasca?
No. Lithium combined with serotonergic psychedelics has been linked to seizures and other serious adverse events, and it is treated across the field as an absolute contraindication rather than a timing question.
Can I take painkillers before an ayahuasca ceremony?
Paracetamol and ibuprofen are generally not problematic. Tramadol, pethidine and fentanyl are serotonergic and must be avoided. Always disclose painkillers during screening, including ones you take only occasionally.
Does a family history of psychosis exclude me?
A first-degree relative — parent or sibling — with schizophrenia or a psychotic disorder is treated as an exclusion at Holistika Center, even where you have never had symptoms, because vulnerability to psychosis is substantially heritable and an induced episode can persist.
Take this list to your health evaluation call and go through it line by line, including the things you take rarely.
Ritshi Zenati, Speaker & Life Coach
Founder at Holistika Center.
Holistika Center holds plant medicine retreats across Barcelona, Málaga, Mallorca, Switzerland, Germany, Norway, Colombia and Mexico.
Also, different programs like Microdosing, Life and Spiritual Guidance, etc.
Visit Holistika Center to explore upcoming programs.
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