Published on May 17, 2021 • Last updated November 11, 2022 Written by Nick Jikomes, PhD

Disclaimer: Psilocybin is a potentially illegal substance, and we do not encourage or condone the use of this substance where it is against the law. This guide is designed to ensure the safety of those who decide to use the substance legally.

Psychedelic mushrooms, or magic mushrooms, belong to the genus Psilocybe. These fungi are capable of producing psilocybin, a compound associated with psychedelic effects. But how much psilocybin is actually found in the most common Psilocybe species, and how should you think about dosing dried magic mushrooms or psilocybin-containing products?

What is the active drug in magic mushrooms?

Psilocybin is not the active drug in magic mushrooms. It is what’s known as a prodrug: A biologically inactive compound that can be metabolized by the body to produce an active drug. If you consume magic mushrooms, psilocybin is metabolized into psilocin. Psilocin is the active compound that causes psychedelic effects. These effects come from psilocin’s resemblance to a neurotransmitter in the brain, serotonin.

How much psilocybin is in magic mushrooms?

Each bar represents the average total psilocin content for different species of Psilocybe mushrooms. Vertical lines on each bar represent variance across samples. Data were compiled from Study 1, Study 2, and Study 3. Like cannabis plants, the chemical content of magic mushrooms varies. Two randomly selected Psilocybe mushrooms, even from the same species and harvest, can have different psilocybin levels. Lab testing is the only way to know precisely how potent a given mushroom is.

Most magic mushrooms people encounter have not been lab tested due to the absence of a legal, regulated environment for doing so. However, there is some published data on the psilocybin content of common Psilocybe mushroom species and we can use this to inform dosing guidelines.

The most common species of magic mushroom is Psilocybe cubensis. Published research on the psilocybin content of Psilocybe mushrooms has shown they can contain roughly 0.5 – 1.0% total psilocin, averaging around 0.7% by weight; 0.7% total psilocin equates to about 1% psilocybin. But remember: Psilocybin content varies a lot from sample to sample within the same species. It also varies between species.

What effects will different doses of psilocybin have?

Let’s assume you have some type of magic mushrooms containing 1% psilocybin. How much mushrooms, by weight, might you consume to get weak, medium, and strong effects? For each level of effects, we’ll estimate the psilocybin content and describe potential effects, from what experienced psychedelic consumers report and also results published in human clinical trials.

Low dose: Amount: 1 gram

One gram of magic mushrooms is commonly considered a low dose that still produces noticeable effects-Please note that this dose is not the same as “micro-dose.” Learn more about microdosing here. These usually aren’t full-blown psychedelic effects with overt visuals or a break from consensus reality; you’re more likely to report euphoria and an enhancement of the senses, such as seeing more vibrant colors. At 1% psilocybin content, this would be 10 milligrams (mg) psilocybin. Note: This should not be considered a microdose; it is a low, noticeable dose.

Medium dose: Amount: 1.75 grams

If you have an eighth-ounce of magic mushrooms—a common quantity—and consume half of it, that would be 1.75 grams, or about 17.5 mg total psilocybin. You will likely experience some psychedelic effects, including open- and closed-eye visuals, synesthesia (blending of the senses), and a heavier euphoria. However, you may not experience a complete dissolution of your normal sense of self, or the truly mind-blowing effects people report from higher doses.

High dose: Amount: 3.5 grams (an eighth-ounce)

An eighth-ounce, or 3.5 grams of dried mushrooms, will have around 35 mg psilocybin content. Ready or not, you’re going to have a full-blown psychedelic experience that will include heavy perceptual and cognitive distortions. You may or may not be able to hold a conversation or accurately perceive your surroundings, especially at the peaks, which often come in waves. No two trips are exactly alike, but you’re pretty much guaranteed to look back on this as a stand-out experience of your life. It is not advisable to take a high dose unless you have a safe, supervised setting to take them in.

Ultra-high dose: Amount: 5 grams

The late Terrence McKenna famously described the “heroic dose,” his preferred way of diving into the full depth of the mushroom experience: Five dried grams of mushrooms in silent darkness. At 1% psilocybin content, five grams will contain about 50 mg of psilocybin. At this dose, there’s not much you can do but lay down somewhere comfortable and let the experience wash over you. “You” won’t really be there once it hits. It will most likely be overwhelming, perhaps bizarre, and indescribable. Taking a dose this large is rare. Few people, even experienced psychonauts, ever take this much. It is not advisable to take even close to this dose without significant experience and an ultra-safe, comfortable setting.

Clinical trial results

How do the doses and descriptions above compare to what has been observed in controlled, human clinical trials? In some of the pioneering psilocybin studies done at Johns Hopkins University, controlled doses of psilocybin were administered to patients. The studies gave people a range of psilocybin doses and generally found that high doses often induced a “mystical-type experience,” the formal research definition for what we might call a “full-blown psychedelic experience.” The doses given to induce such effects were in the 20-30 mg range for psilocybin, or between the medium and high doses in the dosing guide above. In other words, a full eighth-ounce, or 3.5 grams, of dried P. cubensis is likely to contain more psilocybin than the doses given to reliably induce mystical-type experiences in controlled human studies.

How to take magic mushrooms

As always, the mantra for trying a new psychoactive drug is: “Start low, go slow.” Aside from a micro-dose, start with no more than one gram of dried mushrooms, or 10 mg of psilocybin. You can increase your dose every 25 minutes or so. Only experiment with higher doses once you feel comfortable at a low dose. It’s also important to take psilocybin in a safe, comfortable setting, preferably with someone to watch over you or even professional human support in case of any difficulties, as was the case in the Johns Hopkins studies. The experiences one might have with psilocybin or other psychedelics are very sensitive to your mental and physical state, and environment—what’s known as “set and setting.”

Once you get into the “medium dose” range or higher, it’s important to be extra mindful of what you’re dealing with. Remember: you may never be the same again. Patients from the Johns Hopkins studies often reported their 20-30 mg experiences to be among the most important of their lives, comparable in significance to the birth of their first child.

Do mushroom caps or stems have more psilocybin?

Bars representing the average total psilocin from caps and stems of Psilocybe cubensis samples. Vertical lines on each bar represent standard deviation. Caps have higher total psilocin levels on average, but there is a lot of variation from sample to sample. Some consumers swear that either the caps or stems of magic mushrooms are more potent.

There is a small amount of published data on this: Combining data from this study and this study, we can see that P. cubensis caps tend to have a higher total psilocin content than stems, on average. However, there is significant variability among samples and a lot of overlap between caps and stems, so it is not a very reliable rule. More research needs to be done on this topic.

What’s the best way to store magic mushrooms to preserve potency?

A 2020 study found that psilocybin degraded over the course of 15 months of storage, with different rates of degradation depending on temperature and lighting conditions. Psilocybin content was best preserved when mushrooms were stored at room temperature in the dark. Psilocybin degraded the most when mushrooms were stored at very cold temperatures. In all cases, psilocybin degraded over time. It can fall significantly within just one month. Fresh mushrooms will be the most potent.