Collage of Mushroom Illustration and Skeleton Illustration

An Introductory Guide to the Risks of Poisonous Fungi 

Fear: Bad. Caution and knowledge: Good.

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In recent years, foraging for mushrooms has become increasingly popular for many who seek fungi to sate their appetite, explore new flavors, or heal their pains — but it is important to be aware that foraging mushrooms isn’t without its risks. 

Fungi have an impressive alchemical repertoire capable of creating a diverse array of chemicals for decomposition and defense. We are just beginning to get a sense of their chemical accomplishments, and while some of their compounds can be life-changing in a variety of ways, some can also cause significant health issues. 

It’s sad to say, but many of us have grown up in cultures that perpetuate a fear around foraging fungi, with references to oozy, slimy toadstools — a narrative that implies most fungi are poisonous. The purpose of this article is not to further incite fear around foraging for fungi, but simply to provide information to help prevent mushroom poisoning.

… but can I eat it?

While researching the fungi you are interested in, it is advisable to research mushroom species local to you, consult with experienced foragers in your area, and avoid consuming any mushrooms unless you are 100% certain of their identity. Given the huge number of species (and we possibly have only named and described 10% of possible species out there!), learning to ID mushrooms can be overwhelming and confusing.

READ: How to Identify Magic Mushrooms: Step-by-Step

Traditionally, mushroom identification has been a skill passed down across generations, parent to child or grandparent to grandchildren, almost as an inheritance. As our food systems have evolved and changed, a lot of traditional knowledge has been lost to the safety and reliability of consumerism. 

Many of us find ourselves, therefore, learning on our own, relying on generalized ID books or borrowing books from libraries that may be out of date. While that’s a perfectly fine strategy, it is important to note that fungi will sometimes look different from the photo presented in a guide — the author may have selected an ideal example, the image may not have translated well into print, or the fungi itself may be quite variable in appearance. (Many an Australian forager who goes looking for P. subs will happily tell you about the numerous varieties that exist.) If you can, refer to multiple guidebooks; numerous books have been published over the centuries with beautiful and taxonomically accurate illustrations showing the features necessary for identification, so the more sources you can consult, the better.

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Common Poisonous Mushroom Identification Myths

Uncertainty about mushrooms versus toadstools is rife, with numerous little quips or rhymes that suggest what is edible, what is not, and what is poisonous. In some of the rhymes, the author claims the mushroom is poisonous if:

  • A silver spoon (or silver coin) turns black when placed in a pan while mushrooms are cooking.
  • An onion will turn black when placed in a pan while mushrooms are cooking.
  • The skin of the mushroom cannot be peeled.
  • The mushroom is bitter, or burns your mouth when you taste it.

There are many, many more, and importantly, none of them are true! There is no simple test that can be performed to determine if a mushroom is edible or not. The only way to know if a mushroom may be edible is to know the species really well through cultural knowledge and experience. 

READ: The Trippy Truth About Amanita muscaria, The World’s Most Famous Mushroom

Mushroom Identification Basics

As foragers, we need to take responsibility not only for ourselves, but also those who are foraging with us, and for those who may also share our bounty. We need to be aware that various poisonous species may potentially grow right next to what we are foraging. This is particularly true when we are foraging for medicinal species such as Psilocybe: numerous lookalike species share the same ecologies, which is the root of the whole “little brown mushrooms” problem, i.e., many of the Psilocybes are described as ‘LBMs.’  While cubensis are large, robust mushrooms mostly found growing out of cow pats, many others grow from grass or on wood amongst species that, to the unfamiliar eye, may be easily mixed up. 

Picking the wrong mushroom, then realizing a mistake has been made might as well be a rite of passage for every forager, and it is important to note that experienced foragers or mushroom enthusiasts do occasionally make mistakes. While learning to identify mushrooms, you are advised to get a few sets of eyes to confirm or deny your ID.

Some other guidelines:

  • Ignore all the folklore, or at the very least, treat it with great skepticism: most of it comes from before a scientific appreciation of fungi.
  • Be careful about generalizations when it comes to species identification.
  • Only trust knowledgeable people with identifications.  If ID-ing online, get at least three or four IDs from people on your list of trusted identifiers. Even experts can give a wrong ID, so it’s always a good idea to consult multiple resources.
  • Different species of fungi can grow together, with poisonous and edible types in the same spot.
  • Beginner foragers should always be cautious with little brown mushrooms.
  • Poisonous and edible mushrooms occur in the same genus, like Amanita.
  • When traveling, don’t make assumptions about the fungi that look like those at home.
  • When trying a new mushroom, only sample a little bit in case of allergic reactions.
  • Don’t consume old or unpleasant-looking mushrooms.

A Few Notable Mushroom Toxins

Many mushroom toxins are unknown. Poisons exist on a spectrum, and as the saying goes,  “the difference between a poison and a medicine is a question of dosage.” Some are gastrointestinal irritants, others can cause serious harm, some will kill, and a small group will alter your consciousness — yes, we still refer to these as poisonous, particularly if it was unintentional. 

It is important to note that even if the mushroom is a well-known edible, individual responses — these may be due to an allergy or an inability for our bodies to process a particular compound — to each mushroom may also need to be considered.

Some mushroom toxins are a significant threat to human health due to the damage they may cause. They may disrupt crucial processes within the body or begin to damage a crucial organ. If a sufficient amount of the poison is consumed, the damage may not be reversible, leading to death. This is why so many warnings particularly target caution with respect to children (and small animals), because of how vulnerable they are to poisons compared to adults. A dose of α-Amanitin that might destroy a third of the cells of an adult-sized liver may be the same number of total liver cells in a child’s liver — the adult would survive, but the child would not.

We cannot list all the toxins known to be found in mushrooms. The most notable toxins found in toxic mushrooms include amatoxins and phallotoxins, but Orelline and Gyromitrin are also worth mentioning. Some people also include muscimol and related compounds in their summary of toxins.

Amatoxins

Amatoxins are highly toxic compounds. There are at least nine amatoxins which are found in three genera, Amanita, Galerina, and Lepiota, and one species of the genus Conocybe (Pholiotina). Amatoxins damage the liver and kidneys, causing symptoms such as abdominal pain, vomiting, diarrhea, and, in severe cases, liver failure and death. Amatoxins are responsible for the majority of mushroom poisoning fatalities. The first symptoms of poisoning generally begin several hours after consuming, beginning as gastrointestinal distress which passes in time, then after a day or two, kidney and liver failure followed by death. The period following the initial gastrointestinal distress is problematic as people may think they are otherwise OK.

Phallotoxins

Phallotoxins are less toxic than amatoxins but can still cause gastrointestinal symptoms. At least seven phallotoxins are found in Amanita phalloides, the Death Cap. They affect cell membranes and can lead to cell death.

Orellanine

Orellanine (or orellanin) is found in the genus Cortinarius, in section Orellani. This poison resembles the amino acid lysine. It is absorbed by the kidneys, where it disrupts their structure and function. This toxin disrupts the delicate filtration process, causing waste products to build up in the blood and leading to kidney failure. The poisoning is problematic due to symptoms not appearing for generally two to four days, but up to 14 days after ingestion. The first symptoms resemble the common flu, possibly including nausea, vomiting, stomach pains, headaches, and myalgia. These are followed by early stages of kidney failure and eventually decreased or nonexistent urine output. If symptoms are left untreated, this leads to death. 

Gyromitrin

Gyromitrin is a toxin found in the genus Gyromita, a well-known lookalike for Morel mushrooms. This toxin is metabolized in the body and converted into monomethylhydrazine, a potent convulsant and carcinogen. Symptoms of poisoning can include nausea, stomach cramps, and diarrhea, while in severe cases, convulsions, jaundice, or even coma or death. Gyromitrin is mentioned here for those wanting to forage for morels in the spring.

Identifying mushrooms, in general, can be challenging, especially if you have not been exposed to many fungi before. Fungi often share physical characteristics, with poisonous species being present in the same genera as edible varieties. It is, therefore, important to exercise caution and seek expert knowledge when foraging for wild mushrooms. Some poisonous mushrooms, such as the Amanita phalloides (Death Cap) and Gallerina marginata (Death Bells), are particularly dangerous and can be lethal even in small quantities.

If someone ingests a poisonous mushroom, it is essential to seek medical attention immediately. Treatment may involve supportive care, administration of activated charcoal to limit toxin absorption, and in severe cases, liver transplantation.

Notable Species of Poisonous Fungi

There are many poisonous fungi — too many to list here in their entirety — so this list includes the more notable species you are likely to come across while foraging.  We will begin with Amanita phalloides, also known as “Death Caps,” a gilled mushroom from the genus Amanita, the same family as the Fly Agaric (Amanita muscaria) and the Panther Cap (Amanita pantherina). Those two mushrooms are described as being from section Amanita, while the death cap is from section Phalloidae.

Amanita phalloides, aka the Death Cap

Photograph of Mushroom in Nature
Amanita phalloides. Image Courtesy of Gljivarsko Drustvo Nis via WikiCommons.

The term “Death Cap” tends to be used quite generically but is notably the common name for Amanita phalloides. This mushroom is generally greenish to yellow, although in some cases white — because of the variability, the cap color is not a reliable feature to refer to for identification.

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The stem and gills are white, the gill attachment being free. They are an ectomycorrhizal species growing in association with oak, chestnut, or pine, and typically appear from autumn into winter, although can appear at other times of the year. They are widely distributed across Europe, but have been introduced to many parts of the world through the cultivation of various ornamental trees.

Amanita virosa aka Destroying Angel

Photograph of Mushroom in Nature
Amanita virosa. Image Courtesy of WikiCommons.

Another species from the genus Amanita to be aware of is Amanita virosa, commonly  known as the Destroying Angel. This species occurs in Europe, the eastern United States, and Asia. Like other Amanita, it is associated with various deciduous and coniferous trees, with mushrooms appearing in summer and autumn. The cap, stipe, and gills are all white in color. Like many Amanita, immature specimens can resemble edible species commonly foraged by humans, hence the regular efforts to educate people about accidental poisoning. 

Amanita phalloides and Amanita virosa are two of the most poisonous of all known mushrooms, with one cap being enough to kill an adult human (the principal toxic constituent, α-Amanitin damages the liver and kidneys, usually fatally). They are both from Amanita section Phalloidae, which contains other species also known to contain amatoxins. It is best to avoid foraging Amanita or white-gilled species until you have gained some experience telling them apart.

Galerina spp.

Photograph of Mushroom in Nature
Galerina sp. Image Courtesy of Bernard Spragg via Flickr.

People foraging wood-loving species of Psilocybe should avoid collecting Galerina. This group of fungi contains some extremely poisonous species, which are occasionally confused with Psilocybe. They are typical of the “little brown mushroom” classification that is often referred to by some foragers, and it is worth noting that Galerina can grow in exactly the same habitats, and can grow next to or among the target species.

Galerina spp. are typically small, have brown to caramel-brown hygrophanous caps (meaning the caps can change color), and can resemble numerous Psilocybe. However, Galerina can be distinguished by their slender and brittle brown stems and annulus. Galerina can resemble young specimens of wood-loving Psilocybe. They have a rust-brown spore print. Many (not all Galerina) contain α-Amanitin and other amatoxins, the same toxins found in Death Caps, Amanita phalloides.

Galerina are found in temperate regions of the world, with over 300 species. The most well-known species is Galerina marginata (also known as “autumn skullcap,” “deadly galerina,” etc.). They are often found growing on wood in habitats as diverse as forests and urban parklands. They prefer mossy habitats when on the ground but will grow among woodchips.

Psilocybe lookalikes

There are many Psilocybe lookalikes, and to the untrained eye, it can be easy to confuse a Psilocybe with a number of similar genera. Lookalike species include poisonous species from genera such as Galerina, Cortinarius, Conocybe, Pholiotina, Hypholoma, and Leratiomyces; and species that may not harm you but are worth avoiding, such as Tubaria, Pholiota, Agrocybe, and Gymnopilus

Many of these species share similar or the same habitats, which can make foraging tricky for the beginner, particularly when foraging from woodchipped beds. In some cases, Galerinas are associated with moss, so this can make identification a little easier based on ecology, but they are also known to populate woodchipped beds — caution is advised.

Cortinarius spp.

Cortinarius has been mentioned above in the context of the toxin Orellanine, which is found in the Cortinarius section Orellani. Cortinarius spp. are commonly reported as lookalikes of Psilocybe spp., particularly those with brown caps. Some species of Cortinarius have a blue coloring that fades over time, resembling blue bruising; in conjunction with brown caps, these can look very Psilocybe-like. Cortinarius spp. have rust-brown spores.

Conocybe spp.

Species of Conocybe are relatively common and often found growing in lawns, in grasslands on dead moss, on dead grass, on decayed wood, and dung. Most species have long, thin, fragile stems. The Latin name refers to the cone-shaped cape, with common names such as “dunce caps” or “cone heads” due to their conical or bell-shaped caps. Although some species are known to contain psilocybin and psilocin, Conocybe is included here because Conocybe filaris, a common lawn mushroom, contains amatoxins, the same deadly toxins as the death cap.

Pholiotina spp.

This genus is included here by virtue of Pholiotina rugosa, which is another name for Conocybe filaris. Because it is a deadly species, it is helpful to be aware of both names, although in most field guides, this species is known as Conocybe filaris. Pholiotina is noteworthy because it includes the psychoactive species Pholiotina cyanopus and Pholiotina smithii.

Hypholoma spp.

Less poisonous but also of note are Hypholoma spp., which can also look similar to Psilocybe spp. They tend to have brown caps with white stems and a purple-black spore print. Some species can be poisonous. Hypholoma marginatum and Hypholoma fasciculare are two well known lookalikes. Hypholoma fasciculare grows in dense clusters, which is uncharacteristic of Psilocybe

Leratiomyces ceres

Leratiomyces ceres, also known as “woodchip cherry,” has an orange-red cap. These mushrooms retain their veil remnants at the margin and on the surface. They have grayish gills, and their stem is orange-red or pale yellow. They have a purple-black spore print and are poisonous.

Identifying Psilocybe species

There is no one feature that will 100% distinguish a Psilocybe mushroom.  All species in Psilocybe (except one, Psilocybe fuscofulva) contain psilocybin and psilocin, so therefore have the potential to bruise blue; in fact, it’s one of their most discernible characteristics. 

It is important to note that bruising may take little time to appear in some specimens. Some species barely bruise, such as Psilocybe semilanceata, but species such as Psilocybe cubensis or species in Section Subaeruginosae such as Wavy Caps, Flying Saucers, or “P. subs” bruise readily. It is important to be aware that other species also bruise blue, a great example being blue bruising “boletes,” or Mycena species that bruise blue.

Other helpful features, though not specific to Psilocybe, are the tough fibrous stems, and notably the separable gelatinous pellicle. The presence of these, along with other characteristics of your target Psilocybe, are needed to make a safe identification. Psilocybe species can vary, so it is advised to get to know the general description of the species that grow in your area and, if possible, the descriptions of potential lookalikes.

Another helpful identification technique is to make a spore print. Psilocybe have purple-black spores. There are lookalike species with similar colored spored prints (Hypholoma and Leratiomyces both have purple-black spore prints), it is important to avoid making a guess about a species’ identity based on a spore print alone.

How to make a spore print

To make a spore print, you simply remove the cap of a harvested mushroom and place it face-down under a cup on a piece of foil. Within 24 hours, spores will have fallen onto the paper in a unique pattern. (Learn the specifics on making a proper and safe spore print here.) Psilocybe spores should be purple-black in color. In addition to purple-blue spores — a featured shared by some poisonous lookalikes mentioned above — it’s also important to look for other discernible features, like a separable pellicle and fibrous stems. Post photos to Shroomery for identification help or local Facebook Psilocybe groups.

Being Safe With Psilocybe

While mushrooms from the genus Psilocybe are known not to be poisonous, there are some things to keep in mind. The accidental consumption of Psilocybe is still formally considered poisoning — keep your stash somewhere secure, away from children and pets, and somewhere they won’t get confused with other food products. Being careful with dosing is also important, as some batches may be much stronger than others, and can catch people off guard — that museum dose meant for a fun afternoon out could go bad if the dose is much much stronger than expected.

With wood-loving (lignicolous) species it is important to keep in mind “wood-lover’s paralysis” (WLP). WLP is a toxidrome caused by mushrooms from the genus Psilocybe that grow on wood. People experience a loss of muscle strength and motor control that can persist into the following day. It begins as a muscle weakness that turns into paralysis. The effect is temporary, usually wearing off after 24 to 48 hours. For the unprepared, it can be an anxiety-inducing experience. This paralysis should not be confused with the overwhelming effects of a strong dose, as it can occur at relatively low levels of psychedelic intensity. WLP is a distinct physiological effect. 

If you experience WLP, notify those around you or contact someone you feel comfortable with to let them know. Because WLP can cause problems with breathing, if you are trip-sitting for someone else and they report WLP symptoms, take note of their ability to breathe. If they show signs of breathing difficulty, call an ambulance.

If in Doubt, Throw It Out

The most important thing to keep in mind is: If in doubt, throw it out. As well as getting to know the species you are looking for, get to know the potential lookalikes. If you think you have been poisoned, phone your local emergency hotline. You can access additional information about poisoning by calling your local poisons hotline.

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DoubleBlind is a trusted resource for news, evidence-based education, and reporting on psychedelics. We work with leading medical professionals, scientific researchers, journalists, mycologists, indigenous stewards, and cultural pioneers. Read about our editorial policy and fact-checking process here.

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DoubleBlind Magazine does not encourage or condone any illegal activities, including but not limited to the use of illegal substances. We do not provide mental health, clinical, or medical services. We are not a substitute for medical, psychological, or psychiatric diagnosis, treatment, or advice. If you are in a crisis or if you or any other person may be in danger or experiencing a mental health emergency, immediately call 911 or your local emergency resources. If you are considering suicide, please call 988 to connect with the National Suicide Prevention Lifeline.

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