The Fadiman protocol: one day on, two days off

Among microdosing protocols, the Fadiman protocol is probably the best known. It's simple, easy to remember, and built around one idea: leave enough space between intakes to observe. Here's how it works, and how to approach it sensibly.

In short: the Fadiman protocol is a microdosing schedule of one dose day followed by two days without, repeated for several weeks and then paused. It was popularised by the American psychologist James Fadiman. BIEN's own protocol is inspired by it, with two fixed dose days a week.

Where does it come from?

The protocol is named after James Fadiman, an American psychologist who popularised this simple schedule and collected accounts from people who followed it. It isn't a medical protocol or an official recommendation: it's a practical framework that grew out of informal observation.

Fadiman described the approach in his book The Psychedelic Explorer's Guide (2011), and the schedule then spread widely on online microdosing forums. Its appeal lies less in a specific amount than in its structure: a fixed rhythm, rest days and written observations.

The principle: one day on, two days off

The rhythm is a three-day cycle:

Day	Intake	What you do
Day 1	Microdose	Go about your day as usual
Day 2	None	Notice how you feel the day after
Day 3	None	Back to baseline, observe again
Day 4	Microdose	A new cycle begins

In practice, that means a microdose roughly twice a week, and never two days in a row.

Why the rest days?

Two reasons are usually given:

• Limiting tolerance. Sensitivity to psilocybin tends to drop quickly with repeated intakes. Spacing them out helps avoid that.
• Observing clearly. The days without an intake give you something to compare with. Some people say they notice more on the day after than on the day itself.

For how long?

The cycle is usually followed for a few weeks, often described as four to eight, and then followed by a break of several weeks. That pause is part of the protocol: it gives you distance to decide calmly whether you want to continue. The BIEN 2-6-2 protocol is inspired by this rhythm: two microdoses a week for six weeks, then a two-week break.

A sample Fadiman protocol schedule

Because the cycle lasts three days and a week has seven, dose days move around the calendar. If you start on a Monday, the first two weeks look like this:

Week	Mon	Tue	Wed	Thu	Fri	Sat	Sun
1	Dose	Rest	Rest	Dose	Rest	Rest	Dose
2	Rest	Rest	Dose	Rest	Rest	Dose	Rest

Some weeks have three dose days, others two. This shifting pattern is the main practical difference from the BIEN protocol, which fixes two dose days a week.

Fadiman protocol or BIEN 2-6-2?

	Fadiman protocol	BIEN 2-6-2 protocol
Rhythm	One dose day, two days without	Two fixed dose days a week
Dose days	Move across the week	The same each week, for example Monday and Thursday
Cycle length	Often described as four to eight weeks	Six weeks
Break	Several weeks	Two weeks

Neither is a medical protocol. Choose one rhythm, stick to it for the whole cycle and don't switch halfway: changing mid-cycle makes your notes harder to interpret.

What amount?

The principle of microdosing is to stay below the threshold of noticeable effects. For fresh psilocybin truffles, that generally means 0.5 to 1 g per intake. Start at the bottom of the range (0.5 g, half a BIEN truffle) and only adjust in small steps, never beyond 1 g. If you clearly feel perceptual effects, the dose is too high for a microdose.

Fadiman protocol directions, step by step

1. Before you start, read the precautions below, check the law in your country and talk to a doctor.
2. Choose a start day: a calm day, with no obligations and no driving.
3. Day 1: take your microdose in the morning, then go about your day. Note the time and the amount.
4. Days 2 and 3: no dose. Write a few lines each evening all the same.
5. Day 4: the next dose day, and so on until the end of the cycle.
6. At the end of the cycle: take a break of several weeks and reread your notes before deciding whether to continue.

Keeping a journal

Taking notes is at the heart of the protocol. A few lines a day are enough:

• time and quantity taken;
• quality of sleep;
• energy, mood and concentration, on a simple scale from 1 to 5;
• anything unusual, pleasant or not.

After a few weeks, reading these notes back gives a more reliable picture than memory alone. It also keeps you honest: some days are good for reasons that have nothing to do with microdosing. Our guide to keeping a microdosing journal suggests what to track.

What people describe

People who follow the protocol sometimes describe feeling a little more focused, present or inspired. Others notice nothing. These are subjective accounts, not guaranteed effects. Placebo-controlled studies published in 2021 and 2022, including one by Szigeti et al., suggest that expectations play a major role in what people report. Research on microdosing remains preliminary, and the results are mixed.

A few good habits

1. Start on a quiet day, with no obligations.
2. Don't change anything else at the same time (new diet, new sport): otherwise you won't know what's what.
3. Stick to the rhythm: no extra intakes, no "catching up".
4. Respect the breaks, including the longer pause at the end of the cycle.
5. Stop if something doesn't feel right, and talk to a doctor. See also possible side effects and who should not microdose.

Important: psilocybin truffles are for adults (18+) only. They are not recommended during pregnancy or breastfeeding, if you or a close relative has a history of psychotic or bipolar disorders, if you have a heart condition, or if you take any medication (especially antidepressants or lithium). Do not drive after taking them and do not combine them with alcohol. Talk to your doctor first.

Psilocybin truffles are sold legally in the Netherlands, where BIEN is based. Their status varies from country to country: check the law in your own country.

FAQ

How often do you microdose on the Fadiman protocol?

Every third day: one dose day, then two days without. That makes two or three dose days a week, never two days in a row.

How long should you follow the Fadiman protocol?

Cycles are often described as lasting four to eight weeks, followed by a break of several weeks. The break is part of the protocol.

Should you take your microdose in the morning?

Morning is the most common choice. It leaves the whole day to observe how you feel, and any effect will have faded by the evening. BIEN also suggests the morning. More in how long a microdose lasts.

What if you miss a dose day?

Don't double up. Take your next microdose on the next planned day and carry on with the rhythm.

Is the BIEN protocol the same as the Fadiman protocol?

No, but it is inspired by it. BIEN uses two fixed dose days a week, for example Monday and Thursday, for six weeks, followed by a two-week break.

Sources

• Szigeti B. et al. (2021), "Self-blinding citizen science to explore psychedelic microdosing", eLife
• European Union Drugs Agency (EUDA): information on drugs in Europe
• PubMed: scientific literature on psilocybin microdosing