"Amanita muscaria poisoning typically occurs in either young children or people ingesting it for a hallucinogenic experience.[12][46][47] Occasionally, immature button forms have been mistaken for edible puffballs.[48] Additionally, the white spots may be washed away during heavy rain and it can then appear similar to the edible A. caesarea.[49]
Amanita muscaria contains a number of biologically active agents, at least two of which, muscimol and ibotenic acid, are known to be psychoactive. A toxic dose in adults is approximately 6 mg muscimol or 30 to 60 mg ibotenic acid;[50][51] this is typically about the amount found in one cap of Amanita muscaria.[52] However, the amount and ratio of chemical compounds per mushroom varies widely from region to region and season to season, which further confuses the issue. Spring and summer mushrooms have been reported to contain up to 10 times as much ibotenic acid and muscimol compared to autumn fruitings.[46]
A fatal dose has been calculated at approximately 15 caps.[53] Deaths from A. muscaria have been reported in historical journal articles and newspaper reports;[54][55][56] however, with modern medical treatment a fatal outcome would be extremely rare.[57] Many older books mistakenly list it as deadly, giving the impression that it is far more toxic than it really is.[58] The North American Mycological Association has stated there are no reliably documented fatalities in the past 100 years.[59] The vast majority (90% or more) of mushroom poisoning deaths are from having eaten either the greenish to yellowish death cap (A. phalloides) or one of the several white Amanita species known as destroying angels.[60]
The active constituents of this species are water soluble, and boiling and then discarding the cooking water will at least partly detoxify A. muscaria.[61] However, drying may increase potency as the process facilitates the conversion of ibotenic acid to the more potent muscimol.[62] According to some sources, once detoxified, the mushroom becomes edible"
How many dried mushrooms would I have to eat to die from an overdose of psilocybin?
Using the data for rats and accepting a median of 1% potency, it would require the consumption of 1680g of mushrooms to reach the LD50 for a 60kg "rat".
The LD50 stands for the Lethal Dose that is requied to kill half of an exposed population to a particulare agent or drug.
The LD50 for Psilocybin: From the Merck Index 12th Edition
LD50 285 mg/kg i.v.(mice)
LD50 280 mg/kg i.v. (rats)
LD50 12.5 mg/kg i.v.(rabbits)
We most often extrapolate, from rats to humans. So let's stick with convention and use the rat data to compute how many grams of dried mushrooms would be necessary to reach an overdosage of psilocybin.
Psilocybin content in dry mushrooms varies from species to species and ranges from .2 - 2.37%, 2.37 being the highest reported.
Lets take 1% as the median for "average" percentage and use the 280mg/kg i.v. as the LD50.
We must keep in our minds the LD50 considers intravenous dosage and not oral dosages, and that it's done on rats and not humans. Though rats are most often the animal models for humans.
Our question then is, how many mushrooms would one need to eat, if one weighed 60kg to reach the LD50.
Since the dosage is listed as mg/kg, we must multiply our body weight in kg by the LD50.
280mg/kg x 60kg = 16800mg (or 16.8g) of psilocybin. The units of kg cancel by simple math properties and we're left with an amount of pure psilocybin that would be required to kill a "rat" that weighs 60kg.
Since we know the amount of pure psilocybin that it would take to kill a 60kg "rat" and we have a range of psilocybin content present in dried mushrooms, we can now figure out a total dried weight of mushrooms that would be required to reach the LD50.
A simply dimensional analysis problem can be setup to solve this:
?g of mushrooms = 16.8g of psilocybin
16.8g psilocybin / (1g of psilocybin / 100g mushrooms) = 1680g mushrooms.
Thus we've determined that using the data for rats and accepting a median of 1% potency, that it would require the consumption of 1680g of mushrooms to reach the LD50 for a 60kg rat. This amount of mushrooms is enough to provide a "normal" mushroom trip to roughly 650 people.
Some things to keep in mind: Not all data can be extrapolated from rats to humans, but this common practice and generally accepted. Note that the LD50 incorporates route of administration. Therefore our answer of 1680g of mushrooms or 1.68kg of mushrooms is likely an underestimation of the oral dose required to kill a 60kg rat.
With shrooms everything is constantly changing...
