Koh Samui Super Strain (KSSS): Potency, Trip Effects & Dosage

Koh samui super strain[i] is one isolate of a variety of Psilocybe cubensis grown in parts of Thailand. The same name is sometimes applied to a different Psilocybe species that also grows in Thailand, a source of confusion made worse by the fact that many writers do not know the difference between a species, a strain, and a genus[ii]. The result is that publicly-available information about this mushroom may be a bit muddled.

That being said, by all accounts Koh Samui is popular and deserves to be.

Identification and Description

Koh Samui basically looks like most other cube strains, except for being a bit shorter and thicker than most. It’s not distinctive-looking, just a brownish cap with a whitish stem.


Most cubes are pretty non-descript and thus bear a vague resemblance to a great many other non-descript brown mushrooms, some of which are poisonous. Not that they can’t be distinguished by those who know how, but don’t harvest and eat wild mushrooms just because they resemble what your brother’s got growing in a tote in his closet. Fortunately, Koh Samui, as a cultivated strain, is easy to identify; it will be the one the grower gives you saying “here, care to try some Koh Samui?”


In general, a cube is a cube. Its effects are the effects of psilocybin—mood changes (usually pleasant ones), insight, hallucinations (usually subtle, except at higher doses), and sometimes less pleasant things, such as nausea or anxiety. Whether there are differences between strains is a subject of much debate among psychonauts because the course of a trip will be so strongly influenced by other factors, such as set, setting, and dosage that it’s hard to tell how much difference the strain might actually be making. For example, many people report that a Koh Samui trip is unusually pleasant—which might have something to do with said trips often occurring on a beach in Thailand.

Be that as it may, Koh Samui is said to come on very suddenly and to be very mental rather than physical.

Potency and Dosage

Koh Samui is of average potency according to chemical assays, though many users describe it as extremely potent. It’s possible the strain is unusually variable. The smart thing to do with any strain that might be unusually potent is to take a smaller than usual dose.

There’s a common assumption that high-potency strains make for unusually intense trips, but actually you can get any intensity you want from any strain simply by taking a little more. If the trip you take is actually more intense than you wanted, that’s not because the strain is awesome but because you took too much.


Koh Samui doesn’t have any unusual growth requirements. What works for other cubes should work fine for this one. It does grow unusually fast with short colonization times and fruiting times, plus it is unusually resistant to contamination, making it a good choice for first-time growers.

Toxicity, Safety, & Side Effects

There are no known safety concerns for Koh Samui besides those for cubes in general. These are relatively minor but still real.

The most common unwanted side effects of psilocybin are nausea and excessive yawning. Less common but more concerning are anxiety (sometimes severe) and problems with balance and coordination. In rare cases, serious side-effects are possible, such as convulsions, maybe even death. However, as mind-altering experiences go, psilocybin is among the safest, and can be made safer still by following some basic guidelines. For example, have a sober trip-sitter present, do not drive while tripping, and never take more than you need to get the experience you want.

And it is always best to take psilocybin in any form seriously—that means mentally and physically preparing for the experience and then taking the time afterwards to process and integrate it. Not doing the personal work and just using mushrooms for fun is wasteful and potentially dangerous.

There are also other dangers that aren’t caused by psilocybin but are still related. Most obviously, psilocybin is seriously illegal in many jurisdictions, and penalties can be draconian. Find out what the law in your area is before even considering breaking it. Better yet, don’t break it.

Also, the world can be a dangerous place when not fully sober—this is another reason to have a sober trip-sitter. Your sitter can take care of any mundane issues that might pop up and prove difficult for someone busy exploring the up-and-out.


[i](n.d.). Thailand Koh Samui. Mushly

[ii]Lubiano, K. (2024). Koh Samui Mushrooms: All You Need to Know. Tripsitter

Leave a Comment