Mushroom poisoning is a type of food poisoning caused by eating wild mushrooms that contain natural substances that are toxic (poisonous) to humans. Mushroom poisoning is considered an emergency needing immediate medical care.
Mushroom poisonings usually occur for one of three reasons:
Of the more than 5,000 species of mushrooms growing wild in the United States, only about 100 contain compounds that are poisonous to humans, and only about 12 species can cause death. The degree to which a mushroom causes illness depends on the type of mushroom eaten, the amount eaten, and the size of the person poisoned. Toddlers and young children, because of their small size and tendency to put objects in their mouths, are the group most likely to be poisoned, followed by amateur foragers of wild mushrooms. Some poisonous North American mushrooms look like edible European and Asian mushrooms. Consequently, immigrants from Europe and Asia are the most likely foragers to be poisoned in North America.
In 2014, the American Association of Poison Control Centers reported 6,117 exposures to wild mushrooms. Of those exposures 2,196 people were treated in a healthcare facility and 3 resulted in death. In approximately 85 percent of the poisonings, the species of mushroom was not identified. Hallucinogenic mushrooms (Psilocybin and Psilocin) accounted for the majority of identified mushroom poisonings. Mushroom poisoning happens more frequently in Eastern Europe and Asia where wild mushroom hunting is much more common, with most poisonings occurring in the spring or fall.
Mushroom poisoning symptoms can range from mild to deadly. There are two general patterns of symptoms depending on whether the mushrooms contain long-acting or short-acting toxins.
Other species that cause severe, sometimes fatal, illness through longacting toxins include Gyromitra esculenta and Gyromitra gigas (both called False Morel), Verpa bohemica (Early False Morel), and Cortinarius orellanus (Sorrel Webcap).
Symptoms of mushroom poisoning caused by long-acting toxins fall into a three-stage pattern.
Mushrooms that contain short-acting toxins follow a different pattern of symptoms. Typically vomiting begins anywhere from 15 minutes to 2 hours after the mushrooms are eaten. This is often accompanied by heavy sweating, confusion, chills, tremor, loss of coordination, and sometimes breathing abnormalities. Because the person usually vomits soon after eating, fewer toxins are absorbed into the bloodstream. Generally eating a mushroom containing a short-acting gastrointestinal irritant is extremely unpleasant, but results in fairly rapid recovery and no lasting harm.
Hallucinogenic mushrooms, many of which contain psilocybin, have been used for centuries as part of mystical or spiritual experiences or for recreational purposes. These mushrooms, sometimes called magic mushrooms or little brown mushrooms (after their rather ordinary appearance), do not cause fatal reactions. They do, however, cause visual and other hallucinations. Some people experience euphoria, but others experience fear, agitation, and schizophrenia * -like symptoms. Symptoms usually wear off after a few hours. Hallucinogenic mushrooms are usually ingested intentionally. However, if children accidentally eat them, frightening and schizophrenic-like symptoms may continue for up to 72 hours.
Diagnosis of mushroom poisoning is made on the basis of the patient's history; any samples of the mushrooms or vomit containing mushrooms, if available; and symptoms. Diagnosis is difficult if two or more types of poisonous mushrooms have been eaten at the same time, especially if one contains a short-acting toxin and the other a long-acting toxin.
Treatment of long-acting toxins is more complicated. During the vomiting and diarrhea stage, intravenous fluids and electrolytes are given to prevent dehydration and help stabilize body chemistry. Large intravenous * doses of the antibiotic penicillin G are also given. In Europe, Amanita poisoning is treated with silibnin, a product of the milk thistle plant that appears to reduce liver damage by limiting binding of toxin to liver cells. Because of the small number of identified Amanita poisonings in the United States, not enough data are available to satisfy the safety and effectiveness requirements of this treatment for its approval by the U.S. Food and Drug Administration. However, silibnin is sold in the United States as a dietary supplement.
When substantial kidney damage occurs, kidney dialysis * (either temporary or permanent) may be required. Survival after major liver damage requires a liver transplant.
Mushroom poisoning can be prevented by not harvesting and eating wild mushrooms. Commercially grown mushrooms are safe. If one chooses to eat wild mushrooms, they should come from a known, reliable source. Other ways of reducing the chance of mushroom poisoning are to supervise young children and to clear the lawn of any mushrooms as they appear.
It is important for people to remember that many mushrooms that are poisonous in North America look almost identical to safe-to-eat mushrooms found in Europe and Asia, so much so that even experts are fooled. People should collect wild mushrooms in an unfamiliar area only under the supervision of a local expert.
See also Botulism • Food Poisoning • Poisoning
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American Association of Poison Control Centers. 515 King St., Suite 510, Alexandria, VA 22314. Toll-free: 800-222-1222. Website: http://www.aapcc.org (accessed October 28, 2015).
North American Mycological Association. 2019 Ashmore Dr., Ames, IA 50014. Telephone: 515-520-1395. Website: http://www.namyco.org (accessed October 28, 2015).
U.S. Food and Drug Administration. 10903 New Hampshire Ave., Silver Spring, MD 20993. Toll-free: 888-463-6332. Website: http://www.fda.gov (accessed October 28, 2015).
* dehydration (dee-hi-DRAY-shun) is a condition in which the body is depleted of water, usually caused by excessive and unreplaced loss of body fluids, such as through sweating, vomiting, or diarrhea.
* jaundice (JON-dis) is a yellowing of the skin, and sometimes the whites of the eyes, caused by a buildup in the body of bilirubin, a chemical produced in and released by the liver. An increase in bilirubin may indicate disease of the liver or certain blood disorders.
* coma (KO-ma) is an unconscious state, like a very deep sleep. A person in a coma cannot be awakened, and cannot move, see, speak, or hear.
* schizophrenia (skit-so-FREE-neeah) is a serious mental disorder that causes people to experience hallucinations, delusions, and other confusing thoughts and behaviors, which distort their view of reality.
* intravenous (in-tra-VEE-nus), or IV, means within or through a vein. For example, medications, fluid, or other substances can be given through a needle or soft tube inserted through the skin's surface directly into a vein.
* dialysis (dye-AL-uh-sis) is a process that removes waste, toxins (poisons), and extra fluid from the blood. Usually dialysis is done when a person's kidneys are unable to perform these functions normally.