Ayahuasca and Antidepressants: How Long You Actually Need to Stop
Updated: Oct 14
Short answer. For most SSRIs and SNRIs the drug itself clears the body in about one to two weeks. The commonly quoted six-week figure exists because a safe supervised taper takes four to eight weeks, and the washout sits on the end of that taper rather than inside it. Fluoxetine (Prozac) is the genuine exception at four to six weeks, because its active metabolite norfluoxetine has a half-life of 4 to 16 days. Lithium is not a timing question at all — Holistika Center treats it as an absolute contraindication.
I spent an afternoon reading the medical guidelines of five well-known retreat centres. On the same question — how long before ceremony should someone stop an SSRI — I found four weeks, six weeks, six weeks, eight weeks, and "at least six weeks, three weeks after."
None of them explained where the number came from. If you are the person holding a prescription and a booking, that is not a small problem. You are being asked to make a medical decision on the basis of numbers nobody has shown their working for.
So here is the working, from Holistika Center, where we have screened participants for plant medicine retreats since 2017.
Why is combining ayahuasca and antidepressants dangerous?
Ayahuasca is not a single drug. It is a preparation built on two plants doing two different jobs, and the danger comes from the first of them.
The vine, Banisteriopsis caapi, contains harmala alkaloids — principally harmine, harmaline and tetrahydroharmine. Harmine and harmaline are reversible inhibitors of monoamine oxidase A (MAO-A), the enzyme responsible for breaking serotonin down. Tetrahydroharmine, separately, acts as a mild serotonin reuptake inhibitor in its own right.
This MAO inhibition is not incidental. It is the entire reason the brew works when swallowed: without it, the DMT from the second plant would be broken down in the gut before reaching the bloodstream.
Now add an antidepressant. An SSRI blocks serotonin reuptake. An SNRI blocks serotonin and noradrenaline reuptake. Drinking ayahuasca while either is still in your system means doing three things at once:
Blocking the enzyme that clears serotonin — harmine and harmaline
Blocking serotonin reuptake pharmaceutically — the antidepressant
Blocking serotonin reuptake botanically — tetrahydroharmine
The result can be serotonin syndrome: agitation, tremor, muscular rigidity, rapid heart rate, hyperthermia, and in severe cases seizures and cardiovascular collapse. It develops over hours rather than days, and it is not proportional to how well you tolerate either substance alone. Someone who takes their SSRI without side effects and has drunk ayahuasca safely before can still have a serious reaction to the combination.
This is the one area of retreat preparation where there is no room for personal interpretation.
Why do retreat centres give such different timelines?
The four-weeks-versus-eight-weeks disagreement exists because two entirely different clocks are being confused with one another. Almost every published guideline quotes a single number that silently blends both, which is why no two of them match.
Clock one: pharmacological washout
How long the drug takes to physically leave your body. This is governed by half-life — the time for blood concentration to fall by half. A drug is roughly 97% cleared after five half-lives, which is the standard working figure.
For most antidepressants this clock is short. Often startlingly short.
Clock two: the safe taper
How long it takes to come off the medication without triggering discontinuation symptoms or a relapse of the condition it was treating. This is set by your psychiatry and your prescribing history, not by pharmacokinetics, and it is almost always the longer of the two.
Confuse the two and you get "six weeks" with no explanation. Separate them and the guidance becomes usable.
Antidepressant half-lives and washout periods
These figures set the first clock. They are established pharmacokinetics, not retreat-centre convention.
Medication | Class | Approximate half-life | Pharmacological washout |
Fluoxetine (Prozac) | SSRI | 4–6 days; metabolite norfluoxetine 4–16 days | 4–6 weeks |
Citalopram | SSRI | ~35 hours | ~1 week |
Escitalopram | SSRI | ~27–32 hours | ~1 week |
Sertraline (Zoloft) | SSRI | ~26 hours | ~1 week |
Paroxetine (Seroxat) | SSRI | ~21 hours | ~4–5 days |
Fluvoxamine | SSRI | ~15–20 hours | ~4 days |
Venlafaxine | SNRI | ~5 hours; metabolite ~11 hours | ~3 days |
Duloxetine | SNRI | ~12 hours | ~3 days |
Mirtazapine | Tetracyclic | ~20–40 hours | ~1 week |
Amitriptyline | Tricyclic | ~10–28 hours | ~1 week |
Clomipramine | Tricyclic | ~32 hours; metabolite longer | ~1–2 weeks |
Phenelzine, tranylcypromine | Irreversible MAOI | Short, but the enzyme must regenerate | 2 weeks minimum |
Moclobemide | Reversible MAOI | ~2 hours | ~1–2 days pharmacologically |
Two notes on the table. The washout column is pharmacokinetic — roughly five half-lives. Clinical labelling for switching from an SSRI to a psychiatric MAOI uses a longer safety margin of 14 days for most SSRIs and 5 weeks for fluoxetine, which is where the retreat figures of two weeks and five to six weeks ultimately derive from. Fluoxetine is listed at four to six weeks rather than the strict upper-bound arithmetic because that is the established clinical standard.
Read that table and the Prozac exception stops being folklore. Fluoxetine genuinely is the outlier, and it is the outlier because of norfluoxetine — an active metabolite that persists long after the parent drug has gone. Every other SSRI is pharmacologically clear within one to two weeks.
Which raises the obvious question: if sertraline is gone in a week, why does every retreat say six?
Because stopping safely takes longer than clearing
You should not stop an antidepressant in a week, and this is where the second clock takes over.
Abrupt discontinuation produces a well-documented withdrawal syndrome — dizziness, the electric-shock sensations often called brain zaps, insomnia, nausea, irritability, flu-like symptoms and emotional volatility. Paroxetine and venlafaxine are particularly associated with it, precisely because their short half-lives mean blood levels fall fast.
More seriously, stopping abruptly can precipitate a relapse of the depression or anxiety the medication was holding. That is not a minor inconvenience for someone about to sit in ceremony.
Contemporary psychiatric guidance has moved toward slower, non-linear tapering — reducing by progressively smaller increments as the dose gets lower, because receptor occupancy does not fall in a straight line with dose. This approach, usually described as hyperbolic tapering, means the final steps are the slowest ones. In practice a responsible taper runs across four to eight weeks, and considerably longer for someone medicated for years.
Add the washout to the end of that taper and you land at six to eight weeks. That is where the number actually comes from.
The honest formulation: your taper timeline is a medical decision made with your prescriber. The washout sits on the end of it, not inside it. A retreat centre cannot give you a single number, because the first half of the equation is not theirs to set.
The medications where the answer is no, not later
Some medications are not a scheduling problem. At Holistika Center these are handled as exclusions rather than timelines.
Lithium
There is credible evidence of seizures and serious adverse events when lithium is combined with serotonergic psychedelics. Reports have accumulated to the point where the psychedelic research community treats lithium as one of the clearest contraindications in the field. We do not accept participants taking lithium, and we do not treat it as something to be tapered around a booking date.
Antipsychotics and mood stabilisers
These generally accompany a diagnosis — bipolar I disorder, schizophrenia, a psychotic disorder — that is itself a contraindication. The medication is rarely the deciding factor; the underlying condition is.
Bupropion
Less serotonergic than the SSRIs, but it lowers the seizure threshold, and its combination with MAO inhibition carries a hypertensive risk. Not a straightforward washout calculation.
The serotonergic drugs nobody declares
This is where most real-world risk sits, because people report the medication they think of as psychiatric and forget everything else:
Triptans — sumatriptan and the migraine family
Tramadol — a serotonergic painkiller
Dextromethorphan — in cough syrups, labelled DM, DXM or Tuss
St John's wort — sold in supermarkets, pharmacologically serious in this context
5-HTP, L-tryptophan, SAM-e — direct serotonin precursors
Prescribed ADHD stimulants
In our screening calls the person who declares their SSRI and forgets the migraine tablet in their bag is not unusual. It is the norm.
What to ask your prescriber
Most GPs and psychiatrists will not know what ayahuasca is, and some will react to the question rather than to the pharmacology. You will get further by asking the clinical question instead of the retreat question.
"I would like to come off this medication. What taper schedule would you recommend, and over what period?"
"How long after my final dose would the drug and its active metabolites be fully cleared?"
"What discontinuation symptoms should I expect, and when?"
"What would tell us this is not the right time to stop?"
That last question is the important one and the one people avoid. Sometimes the answer is that this is a bad moment to come off, and that answer is worth more than a retreat place.
Restarting after the ceremony
Restarting matters as much as stopping, and it gets far less attention.
The harmala alkaloids are reversible MAO inhibitors, which distinguishes them from classical psychiatric MAOIs and means they clear comparatively quickly — within roughly 24 hours. Despite that, standard guidance is to wait at least two weeks before reintroducing a serotonergic medication, and to do it with your prescriber at a dose they set rather than the dose you were previously on.
There is a second reason to wait beyond the pharmacology, and in my experience it causes more harm than the first.
The weeks after a ceremony are when people feel best and make their least reliable decisions about long-term treatment. Deciding you no longer need medication three days after a retreat is a decision made by the afterglow rather than by you. That state is real, measurable and temporary. Anyone who has stopped psychiatric medication on the strength of a good weekend should be speaking to their doctor, not to their facilitator.
How Holistika Center handles this
Every participant completes a health evaluation call before a place is confirmed, and medication is the first thing we go through — prescribed, over the counter, occasional and herbal.
If someone tells us they stopped their antidepressant without speaking to their doctor, we do not treat that as preparation being complete. We treat it as a reason to slow down, and often to move them to a later retreat. We would rather lose a booking than have someone do something abrupt to their nervous system on our account.
If your medication timeline does not fit the date you were hoping for, move the date. The retreat will run again next month. A compressed taper does not get a second attempt.
Frequently asked questions
How long before ayahuasca should I stop taking an SSRI?
Pharmacologically, most SSRIs clear in one to two weeks; fluoxetine takes four to six weeks because of its long-lived metabolite. In practice the total time is set by your taper, typically four to eight weeks under prescriber supervision, plus the washout at the end.
Can I take ayahuasca while on antidepressants?
No. Combining ayahuasca with SSRIs, SNRIs, tricyclics or MAOIs risks serotonin syndrome, which can be life-threatening. Reputable retreat centres decline participants who have not completed a supervised discontinuation.
Why does Prozac need longer than other SSRIs?
Fluoxetine produces an active metabolite, norfluoxetine, with a half-life of 4 to 16 days. Even after fluoxetine itself has cleared, norfluoxetine continues inhibiting serotonin reuptake, which is why four to six weeks is the standard figure.
Is lithium a contraindication for ayahuasca?
Yes, and an absolute one. Credible reports link lithium combined with serotonergic psychedelics to seizures and other serious adverse events. Holistika Center does not accept participants taking lithium.
When can I restart my antidepressant after a ceremony?
The standard guidance is a minimum of two weeks after the final ceremony, reintroduced at a dose set by your prescriber. Decisions about whether to restart at all should be made after the post-retreat afterglow has passed, not during it.
What if my doctor refuses to discuss ayahuasca?
Ask the clinical question rather than the retreat question — how to taper safely, over what period, and what full clearance looks like. The pharmacology is identical regardless of your reason for stopping.
Medical disclaimer. This article is educational and is not medical advice. Ayahuasca retreats are not medical treatment and are not a substitute for professional care. Never start, stop or change a prescribed medication without the supervision of the doctor who prescribed it.
If you are working through this decision and want a specific conversation about your medication and timeline, book a health evaluation call with us before you book anything else.
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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