What is the Fadiman protocol?

The Fadiman protocol is a microdosing schedule popularized by Dr. James Fadiman. It follows a repeating three-day cycle: one dosing day, then two days without a dose. People typically follow the rhythm for several weeks, then take a longer break.

How long is one Fadiman cycle?

The core unit is three days: a dose day, then two off days. Many people repeat that rhythm for four to eight weeks, then pause for two to four weeks before deciding whether to begin again.

Why does the Fadiman protocol include days off?

The off days are deliberate. They reduce the chance of building tolerance and give you a baseline to compare against, so you can notice what actually changed. Tracking how you feel on the off days is where most of the insight comes from.

What do people take on the Fadiman protocol?

The protocol is a schedule, not a substance. It is most commonly associated with psilocybin mushrooms, but people apply the same one-on, two-off rhythm to other substances too. The protocol describes the timing, not what you take or how much.

June 22, 2026· 7 min read

The Fadiman Protocol: The Classic Microdosing Schedule, Explained

The Fadiman protocol is the most widely followed microdosing schedule, and it is usually the first one people come across. It is named after Dr. James Fadiman, a psychologist who has studied and written about microdosing for years and who gathered informal reports from thousands of people following the same simple rhythm.

This guide explains what the protocol actually is, where it came from, how it compares to the other common schedules, and why the structure matters more than people expect. It is educational only. It is not medical advice, and it does not tell you what or how much to take.

The schedule in one line

The Fadiman protocol runs on a repeating three-day cycle:

Day 1: a dose day. A small, sub-perceptual amount.
Day 2: an off day. No dose. You notice how you feel.
Day 3: a second off day. Again no dose, and again you pay attention.

Then the cycle repeats. Most people follow this rhythm for somewhere between four and eight weeks, then take a longer break of a few weeks before deciding whether to start another round. The shorthand you will see everywhere is "one day on, two days off."

What "microdose" actually means here

The word that does the work in that schedule is sub-perceptual. A microdose is meant to sit below the threshold where you feel obviously altered. The idea is not to have an experience on the day itself, but to go about a normal day and watch for subtle shifts over weeks: in mood, focus, sleep, or how you relate to people.

That is why dose size matters so much, and why chasing a noticeable effect tends to defeat the point. This guide deliberately does not give amounts. Finding a level is personal, it varies by substance and by person, and getting it wrong in either direction is the most common way people end up disappointed.

What people follow it with

The Fadiman protocol is a schedule, not a substance. It describes the timing only.

In practice it is most closely associated with psilocybin mushrooms, which is what most of Fadiman's reports came from. People also apply the same one-on, two-off structure to other substances. The rhythm is the same regardless: the point of the framework is the spacing and the rest days, not the thing being taken.

Where it came from

Fadiman set out the one-day-on, two-days-off structure in his writing on microdosing, then collected self-reported observations from people who tried it across many countries. It became the default reference point for two plain reasons: it is simple to remember, and the built-in rest days make it easier to tell signal from noise. It is closer to careful citizen science than to a clinical trial, and it is worth holding it as exactly that. The reports are real, but they are self-reported, and the formal research is still catching up.

Why the off days matter as much as the dose

This is the part most people miss. The two off days are not a gap in the schedule. They are the schedule.

There are two reasons they are built in:

Tolerance. Taking a dose every single day tends to blunt any effect quickly. Spacing doses out helps avoid that.
A baseline to compare against. If every day looked the same, you would have nothing to measure against. The off days give you a clean reference point, so a good dose day, or a flat one, actually means something.

Tracking how you feel on the off days, not just the dose days, is where the real picture lives. A pattern only shows up when you can see the whole cycle next to itself. This is also the single biggest difference between people who get something out of a protocol and people who give up after a fortnight unsure whether anything happened.

How it compares to other schedules

The Fadiman protocol is one of a few common rhythms, and it helps to know where it sits:

Fadiman (one on, two off). The classic. Conservative spacing, lots of baseline days, easy to read.
The Stamets Stack (four on, three off). A different philosophy that pairs the dose with other ingredients and runs four consecutive days before a break.
Every other day. A simpler alternating rhythm some people prefer, though the tighter spacing leaves less of a clean baseline.

Most people start with Fadiman precisely because the wide spacing makes the early weeks easier to interpret. You can always move to a different rhythm later once you know what you are looking for.

How people run it well

A few things come up again and again:

Consistency beats intensity. The value is in seeing a rhythm over weeks, not in any single day.
Change one variable at a time. Adjusting several things at once makes it impossible to know what did what.
Write things down. Memory is unreliable, especially for subtle shifts in mood, focus, or sleep. People who keep notes get far more out of a protocol than people who try to remember.

Common mistakes

Treating the off days as time off from paying attention. They are the measurement days. Skipping the notes on those days throws away most of the value.
Chasing a feeling. If you can clearly feel it, it is usually not a microdose. Bigger is not better here.
Stacking changes. New supplement, new sleep routine, new protocol, all at once. Now nothing is interpretable.
Stopping too early. A few days tells you almost nothing. The pattern needs a few weeks of a clean cycle to show itself.

Tracking the Fadiman protocol with Dose Days

Dose Days is built around exactly this rhythm. It treats dose days and integration days as different kinds of day, lays the Fadiman cycle out for you, and lets you log a dose with an intention, a mood, and a note in seconds. Over a few weeks the patterns surface on their own, across the whole cycle rather than one isolated day.

It is free to start, all your data stays on your device, and nothing is shared anywhere.

A note on safety and the law

Microdosing involves substances that are controlled in most places, and the research is still early. Nothing here is medical advice or a recommendation to use any substance.

In the United States, psilocybin remains illegal under federal law as a Schedule I substance. A small number of states and cities have changed their own rules in recent years, Oregon and Colorado being the most notable, but the picture varies widely and keeps shifting. Understand the law where you actually live before making any decision.

The health risks are higher, and the interactions less understood, for anyone with a personal or family history of psychosis or bipolar disorder, and for anyone taking other medication. Make informed decisions and speak to a qualified professional about your own situation.