Mushroom poisoning

Mushrooms are a type of fungus#

Many varieties of wild fungus grow in gardens, parks and bushland, and a large number of them are edible.

A few types are poisonous or even deadly#

Contrary to popular belief, there is no home test that can tell edible and poisonous varieties apart. The only reliable way to know whether a wild mushroom is safe to eat is to have it identified by a mushroom expert (mycologist).

If you are unsure whether a mushroom is safe, do not eat it. The safest approach is to eat only mushrooms you have bought from a supermarket, greengrocer or another reputable source.

What to do if poisoning is suspected#

If you suspect that you or your child may have eaten a poisonous mushroom, do not wait for symptoms to appear before seeking help. Contact your local poisons information center straight away. These services usually operate 24 hours a day, every day.

Staff will take a brief history and give you appropriate advice. In some cases you may need to seek treatment at a hospital. It helps to have a sample of the mushroom, and you may be asked to send a photo of it to assist with identifying the species and assessing the risk.

If a person has collapsed, stopped breathing, is having a seizure or is suffering a severe allergic (anaphylactic) reaction, ring your local emergency number (for example 911 in the US and Canada, 112 across the EU and many countries, 999 in the UK, or 000 in Australia) for an ambulance immediately. Do not call a poisons information line in a life-threatening emergency.

The main effects of poisonous mushrooms#

Poisonous mushrooms can produce three main types of effect: hallucinations, gastrointestinal illness, and liver and kidney failure that can lead to death.

Hallucinogenic mushrooms#

Some species contain toxins that cause hallucinations. These psychotropic types are commonly referred to as “magic mushrooms”. One of the better known species is the golden top, which looks very similar to some Galerina mushrooms that are potentially deadly.

Apart from hallucinations, other effects can include:

• confusion
• muscle weakness
• agitation
• rapid heart rate
• headache

Gastrointestinal illness#

Many poisonous mushrooms cause gastrointestinal illness, with symptoms such as:

• nausea
• vomiting
• stomach cramps
• diarrhea

Symptoms can begin from 6 to 24 hours after eating, and in serious cases death can occur within 48 hours.

Liver failure and death#

The Death Cap mushroom (Amanita phalloides) is responsible for about 9 out of 10 fungi-related deaths. Its toxin can fatally damage the liver and kidneys. Other mushrooms that have a similar effect include some species of Galerina, Lepiota and Conocybe.

Two dangerous mushrooms to know#

The Yellow-staining mushroom and the Death Cap are two poisonous mushrooms that can be found in some regions.

Yellow-staining mushroom (Agaricus xanthodermus)#

In some areas this is the most commonly eaten poisonous mushroom. It often grows wild in lawns and gardens and looks very similar to edible mushrooms.

Characteristics include:

• grows on the ground in clusters, often clumped or in “fairy rings”
• the cap is 50–200 mm in diameter
• the cap is usually white, but can turn brown with age
• the cap of young mushrooms looks a little square

When damaged, the cap and stem stain yellow, later fading to a dirty brown. The mushroom can give off a chemical smell, like disinfectant, iodine or kerosene, which can become even stronger when cooked.

If eaten, symptoms can include:

• abdominal cramps, nausea, vomiting and diarrhea, usually within 30 minutes to 2 hours
• dizziness
• sweating
• drowsiness

Less common symptoms include headache.

Death Cap mushroom (Amanita phalloides)#

The Death Cap is potentially fatal if eaten. Characteristics include:

• typically grows under oak trees
• the cap is 40–160 mm in diameter
• the cap ranges in color from pale yellow to green to olive brown
• the gills (ridges on the underside of the cap) are white
• the base of the stem has a membranous “cup”

Symptoms usually begin anywhere from 6 to 24 hours after the mushroom is eaten, and death may follow from liver and kidney damage. A single mushroom can contain enough poison to kill an average-sized adult. Cooking, peeling, drying or soaking the mushroom does not make it safe to eat.

Protect your children from mushroom poisoning#

Most young children who are poisoned find the mushrooms in the garden at home. Children younger than 5 years have a natural tendency to put things in their mouths.

If you have a toddler, check your garden regularly for mushrooms and remove them to reduce the risk of accidental poisoning.

Protect your pets from mushroom poisoning#

Take particular care when walking your pets in areas where mushrooms may grow. Where possible, remove any mushrooms from your yard before pets can eat them. Dogs are more likely than cats to ingest mushrooms.

Pets can develop a range of illness from eating wild mushrooms, from a gastroenteritis-type syndrome to severe, life-threatening disease and death. If your pet has eaten a wild mushroom, contact a veterinarian or your local animal poisons helpline for advice.

Key points#

• There is no home test for telling edible and poisonous mushrooms apart; only a mycologist can reliably identify a wild mushroom.
• If you are unsure, do not eat it, and stick to mushrooms from a reputable source.
• If poisoning is suspected, do not wait for symptoms; contact your local poisons information center immediately, and call for an ambulance in an emergency.
• The main effects are hallucinations, gastrointestinal illness, and liver and kidney failure that can be fatal.
• The Death Cap causes most fungi-related deaths, and cooking or drying does not make poisonous mushrooms safe.
• Check gardens for mushrooms to protect young children and pets.

Where to get help#