MSD Manual

Please confirm that you are a health care professional

honeypot link
Professional Version

Miscellaneous Poisonous Mushrooms


Birgit Puschner

, DVM, PhD, DABVT, Michigan State University

Reviewed/Revised Apr 2022 | Modified Nov 2022

Ramaria flavo-brunnescens

Ramaria flavo-brunnescens is a colorful coral mushroom that is found exclusively in eucalyptus woods in North America, Australia, Brazil, and Uruguay. It is reported to be poisonous to ruminants (cattle and sheep). The toxin is an unknown, volatile compound or compounds found throughout the plant that is reported to interfere with sulfur-containing amino acid incorporation. Drying decreases toxicity.

Clinical Findings of Ramaria flavo-brunnescens Toxicosis in Animals

Clinical signs may appear as early as 3 days or up to 6 days after exposure. They include anorexia, diarrhea, salivation, hyperthermia, depression, hyperemic coronary band, hemorrhage (anterior chamber of eyes), oral ulceration, altered keratinization (hair and hoof loss, similar to selenium toxicosis Selenium Toxicosis in Animals Selenium imbalances are common in production animals. Both acute and chronic selenium toxicosis (or selenosis) occasionally result from supplement overdose; chronic selenosis can also occur... read more ), and recumbency. Death or recovery may be expected in 3–15 days.

Diagnosis of Ramaria flavo-brunnescens Toxicosis in Animals

These mushrooms grow exclusively among eucalyptus plants, so history of exposure to eucalyptus is key. Ergotism Ergotism in Animals Ergotism in animals generally presents as lameness; necrosis of the tip of the tail, ears, and hoof tissue; and decay of the wattle, comb, beak, and feet in birds. Additional adverse effects... read more Ergotism in Animals and selenium exposure can cause similar clinical signs. The duration of signs and clinical outcome help to confirm diagnosis.

Treatment of Ramaria flavo-brunnescens Toxicosis in Animals

Treatment involves removing the affected animal from the source and offering supportive care. Recovery requires time (3–15 days).

Paxillus involutus

Paxillus involutus has a dry or slimy, brownish cap with an in-rolled margin and depressed center. The gills are yellow to light brown and descend a short distance on the brown, smooth stalk. Spores are yellow-brown. Paxillus involutus is widely distributed in North America. It may appear singly or in groups of several, near or on wood in hardwood and coniferous forests and under birch in the spring and fall. The toxin is unknown; however, repeated ingestion can result in a rare autoimmune hemolytic anemia (AIHA) that has a high fatality rate in humans. Because of a similar clinical presentation to amanitin poisoning, it may be confused with amanita poisoning.

Clinical Findings of P involutus Toxicosis in Animals

Intoxications with P involutus typically are associated with gastrointestinal signs of vomiting, diarrhea, and abdominal discomfort, with full recovery over 2–4 days. In rare cases, repeated ingestion of the mushroom stimulates an autoimmune reaction leading to gastrointestinal signs, followed by hemolysis, renal failure, shock, icterus, and disseminated intravascular coagulation (DIC). Multiorgan failure may cause death. Laboratory findings (elevated bilirubin concentration and transaminase activity) and clinical signs of the Paxillus syndrome are similar to amanita poisoning. However, reports of the Paxillus syndrome are rare.

Diagnosis and Treatment of P involutus Toxicosis in Animals

A diagnosis can be made based on mushroom identification and consistent clinical signs. Because the toxin is unknown, confirmatory testing is not possible. Treatment involves supportive measures.

quiz link

Test your knowledge

Take a Quiz!