Mushroom Safety & Interactions

Mushrooms are food, supplements and, in the wild, sometimes poisons. This page puts the urgent points first, then points you to the page that answers each safety question in more detail. It is general information, not medical advice. A pharmacist or clinician who knows your health and your medicines is the right person to decide what is safe for you.

Urgent: if someone may have eaten a wild or unknown mushroom

Call Poison Help in the US at 1-800-222-1222 right away; the poison center also has an online tool. [1] Call 911 if the person collapses, has a seizure, has trouble breathing or cannot be awakened. [1] Do not wait for symptoms to appear. Keep a sample only if the poison center tells you to. This site does not teach identification or foraging; see Mushroom Poisoning: Warning Signs and Urgent Help and Plant and Mushroom Poisoning. For other countries, see Poison Help by Country. Psilocybin ("magic") mushrooms are a different subject, covered in Medicinal Mushrooms vs Psychedelic Mushrooms.

Urgent: liver and kidney warning signs

Liver damage has been reported with some mushroom supplements, and the NIH center for complementary health notes that more cases of sudden liver damage are being reported in people taking dietary supplements generally. [2] Yellowing of the skin or the whites of the eyes is called jaundice and can have several causes, including liver disease and medicines. [3] If that happens, contact a clinician promptly and bring the product label. Kidney injury has been reported with chaga powder. [4] Details are on Mushrooms and the Kidneys, Oxalates and the Liver.

What the sources report, by topic

Evidence here is mostly case reports and small studies, which show that something can happen, not how often. "Natural" does not mean safe. [2]

Quality, labels and contamination

In the US, the FDA does not have the authority to approve dietary supplements before they are marketed. [10] The National Cancer Institute notes that ingredients may vary from lot to lot and that there is no guarantee the label matches the contents. [11] It also notes that mycelium grown on grain can contain large amounts of alpha-glucans from the grain. [11] Processed mycelium is hard to tell apart by eye, so DNA barcoding has been proposed to confirm species. [12] Mushrooms can take up metals; a 2026 study of 164 dried edible mushroom samples found contamination differed by species, supplier and certification. [13] That study looked at food mushrooms, not supplements. See Heavy Metals, Pesticides and Mold and Quality Testing and Certifications.

Species matter

A safety finding for one mushroom does not transfer to another. The reports above involve specific species, such as reishi (Ganoderma lucidum), lion's mane (Hericium erinaceus), chaga (Inonotus obliquus) and shiitake (Lentinula edodes), and each is a different product with different cautions. [14]

Who should ask first

Ask a pharmacist or clinician before using a mushroom supplement if you take prescription medicines, are pregnant or breastfeeding, are giving it to a child, have liver or kidney disease, an autoimmune condition or a transplant, are in cancer care, or have surgery planned. The National Cancer Institute states that the FDA has not approved medicinal mushrooms as a treatment for cancer or any other medical condition. [11] Never stop or change a prescribed medicine on your own; ask the prescriber.

Reporting a problem

Anyone can report a supplement problem to the FDA through its Safety Reporting Portal, ideally after seeing a health care provider. [10] See Side Effects, Allergic Reactions and Reporting.