Dosing

Microdosing THC: How to Find Your Lowest Useful Dose

September 2026 · 11 min read

A microdose of THC is 1 to 2.5mg, small enough that you can still work, follow a conversation and remember the afternoon. The problem is that almost nothing on a dispensary shelf is sold in that size. This is what a microdose does, what it does not do, and how to get one out of a package built around 10mg servings.

The short version

• A THC microdose is 1 to 2.5mg. 5mg is a full beginner dose and 10mg is the standard retail serving, which is 4 microdoses in one piece.
• Inhaled, a microdose is 1 short pull, roughly 2 to 3mg, arriving in under 5 minutes and gone in 2 to 4 hours.
• Swallowed, 2.5mg takes 30 minutes to 2 hours to arrive and runs 6 to 8 hours, so an afternoon microdose is still with you at bedtime.
• Wait a full 2 hours before adding anything. At microdose sizes the second dose is what turns a clear afternoon into a lost one.
• Tinctures are the only common product measurable in 2.5mg steps without cutting anything, at roughly 10mg per full dropper.
• Daily microdosing builds tolerance within weeks. 2 or 3 cannabis-free days a week keeps your dose where it started.

What counts as a microdose: 1 to 2.5mg

A microdose is the amount that produces a mild shift without impairment. In practice that is 1 to 2.5mg of THC for someone with little or no tolerance, and the test is behavioral rather than numerical: if you would not want to be on a work call, it was not a microdose.

There is no clinical definition of a cannabis microdose and no regulator that defines one. The number below comes from where people actually land when they titrate down, not from a standard.

The gap that matters is between 2.5mg and 5mg, because doubling a microdose is what crosses most people from useful to impaired. That gap is also where the evidence on low doses points. A controlled trial at the University of Chicago found that 7.5mg of oral THC reduced stress from a public speaking task while 12.5mg increased it, which is the whole argument for staying low stated as a dose response curve.

"Start low and go slow" is only an instruction when it has numbers on it. Low is 2.5mg. Slow is one change per day, decided the following morning, not 40 minutes later.

Microdose amounts by method: inhaled, edible, sublingual

A milligram number means nothing until you say how it enters the body. The same 2.5mg behaves like three different drugs across these three routes, and only one of them is easy to steer.

Inhaling is the most controllable way to microdose because the feedback arrives before the next decision does. One pull, 10 minutes, and you know exactly where you are. A one-hitter or a small bowl matters here, because a packed bowl invites a second and third pull out of habit rather than need.

Tinctures are the most precise. A 1mL dropper marked in quarters lets you take 2.5mg without cutting, weighing or guessing, and part of the dose absorbs under the tongue and arrives inside 30 minutes.

Edibles are the least suited to microdosing and the most commonly used for it. The CDC puts the delay before effects at 30 minutes to 2 hours, and a 2pm gummy is still working at 9pm. If the point of a microdose is a functional afternoon, an 8-hour product is a poor fit for it.

Why a swallowed microdose hits harder than an inhaled one

Swallowed THC passes through your liver before it reaches your brain. That first pass converts a large share of it into 11-hydroxy-THC, a metabolite that crosses into the brain more readily and is stronger than the THC you started with.

Inhaled THC skips the liver. It moves from your lungs into your bloodstream and reaches the brain largely unchanged, so far less of it is converted along the way. Same molecule, same milligrams, different chemistry by the time it counts.

For microdosing this matters twice. The oral dose is effectively stronger than the number suggests, and the amount converted varies enough between people that 2.5mg is not the same experience for everyone who swallows it. Someone who microdoses flower comfortably can still find 2.5mg eaten to be more than they wanted.

Find your dose over 5 days, not in one night

Your microdose is a number you discover, not one you read off a chart. The chart tells you where to start so the discovery is pleasant, and 5 evenings is enough for most people to land on it.

Take one dose per day at the same time, on a similar stomach, and change nothing else. Write down the milligrams and one line on how it went. If the day was uneventful, add 1mg tomorrow. If you felt more than you wanted, drop back to the last dose that worked and stop there.

The rule that keeps this from going wrong is the 2-hour wait. Nothing gets added inside 2 hours of an oral dose, and nothing gets added inside 15 minutes of an inhalation. Redosing at 45 minutes because "it isn't working" is how a 2.5mg plan becomes a 7.5mg night, all of it landing at once.

5 evenings of this tells you more than any dosing chart, because the variable being measured is you, and the number you land on holds for months as long as your use stays occasional.

Getting a 2.5mg dose out of a 10mg package

Nobody sells you 2.5mg. You buy a package built around a 10mg serving and you do the arithmetic yourself. Colorado caps every retail edible serving at 10mg of THC with 100mg per package, and most regulated states use the same structure, so the math is the same almost everywhere.

Read 4 numbers on the panel: total THC per package, servings per package, THC per serving, and whether the pieces are scored or individually molded. The number on the front of the bag is usually the package total. The per-serving figure, printed smaller, is the one your dose comes out of.

Then divide. A 10mg gummy cut in quarters with a clean knife on a board gives 4 doses of 2.5mg, and the cut is accurate enough at this scale as long as the piece is uniform. A single 100mg cookie does not divide reliably, because the THC is not evenly distributed through baked goods.

Low-dose products remove the cutting entirely. 2.5mg and 5mg pieces exist in most mature markets and rarely make the front display, so the low-dose tins on a Portland dispensary menu are found by filtering for milligrams rather than by browsing.

Ratio products are the other route. A 1:1 or 2:1 CBD to THC tincture delivers a small THC dose inside a larger, gentler product, and these are stocked as a standard menu category across Colorado rather than as a specialty item.

What moves your number up or down

The ladder is a starting point. 5 things shift where an individual lands, and only one of them is under your control on the day.

Body weight matters less than people assume. There is no reliable milligram-per-kilogram rule for cannabis, and a 220-pound person and a 130-pound person should both start at the same 2.5mg.

Microdosing builds tolerance too

A small dose taken every day still builds tolerance. Cannabinoid receptors downregulate with regular exposure regardless of how modest each dose is, so the person who starts at 2.5mg in January can be at 7.5mg by March without noticing the climb.

That climb defeats the purpose. The whole value of a microdose is being below the impairment threshold, and a dose that has quietly tripled is no longer below it.

Tolerance reverses. 2 to 4 weeks off returns most people close to where they started, and even 3 or 4 days makes a difference you can feel. The simpler protection is to build the break in from the start: 2 or 3 cannabis-free days a week keeps a microdose a microdose.

When a microdose is the wrong tool

Sometimes the honest answer is that a small dose will not do the job. If you are using cannabis for sleep, 2.5mg often does not last through the night, and the dose that does is usually well above microdosing range.

It is also a poor fit for anyone with real tolerance. Someone smoking daily will feel nothing at 2.5mg, and the useful move there is a tolerance break rather than a smaller dose.

And it is not a way to make an impairing activity safe. A dose small enough to leave you clear on a work call is still a dose, and driving is off the table either way.

Common questions

Is 2.5mg of THC enough to feel anything?

For someone without tolerance, usually yes, but faintly. Expect a mild mood and body shift rather than a head change, and expect nothing at all on some days depending on food and sleep. 5mg is the dose most people describe as clearly noticeable, which is exactly why it is not a microdose.

How long should I wait before taking a second microdose?

2 hours for anything swallowed, 15 minutes for anything inhaled. Set a timer, because your sense of elapsed time is one of the first things THC alters. If 2 hours pass and you feel nothing, add 1mg rather than repeating the dose.

Why do edibles feel stronger than smoking the same amount of THC?

Your liver converts swallowed THC into 11-hydroxy-THC before it reaches your brain, and that metabolite is more potent and crosses into the brain more easily than THC itself. Inhaled THC bypasses the liver. Same milligrams, different compound arriving.

How much THC is in one hit?

Roughly 2 to 3mg for a short pull from flower or a vape, though the real figure moves with the potency of the product and how deeply you inhale. That is why inhaled dosing is counted in pulls rather than milligrams, and why 1 pull is a workable microdose.

Does body weight affect how much THC you need?

Less than most people expect. THC is fat-soluble, so body composition affects how it distributes and how long traces linger, but there is no dependable weight-based dosing rule. Tolerance and liver enzyme differences swamp body weight as predictors.

Can you build a tolerance from microdosing?

Yes. Daily use at any dose downregulates cannabinoid receptors, and microdosers routinely find their dose has doubled over a few months. Keeping 2 or 3 days a week free of cannabis is the simplest way to prevent it.

How long do edibles take to kick in?

30 minutes to 2 hours, and longer after a heavy meal. A 2.5mg edible follows the same curve as a 10mg one, so the delay is identical even though the effect is small. Plan an oral microdose around 6 to 8 hours, not 2.