Mushroom Toxicity


  • severe toxicity from mushrooms is rare in humans
  • most symptomatic presentations are a self-limiting gastroenteritis requiring supportive care only
  • lethal hepatotoxicity from Amanita mushrooms must be excluded
    — very rare in Australia
    — accounts for most mushroom related deaths worldwide
  • mushroom identification is very difficult and often impossible (e.g. unavailable, decomposing, cooked, partially digested)


  • usually when wild mushrooms are misidentified as an edible species
  • may present as clusters with more than one person poisoned



Gastrointestinal, e.g. many mushroom species

  • toxic mechanisms uncertain
  • GI symptoms with onset 30min-3h and resolution in 6-24h

Cholinergic, e.g. Citocybe and Inocybe species

  • muscarine-mediated
  • 30min-2h: cholinergic syndrome

Hallucinogenic, e.g. Psilocybin spp

  • psilocybin-mediated
  • onset in minutes: anxiety, mydriasis, ataxia, tacycardia, dyskinesia, hallucinations, delirium

Disulfram-like; e.g. Coprinus  spp

  • coprine-mediated
  • <2h of mushroom ingestion with prior ethanol consumption, lasts 6 hours: N&V, flushing, tachycardia, sweating, chest pain

Glutaminergic, e.g. Amanita muscaria and panterina

  • 30min-2h: delirium, dysphoria, drowsiness, haullcinations, myoclonus, hyperreflexia, seizures

Epileptogenic, e.g. Gyromitra spp

  • gyromitrin-mediated symptoms
  • <6h: GI symptoms
  • CNS symptoms: headache, ataxia, fatigue, nystagmus, tremor, bertigo, seizures (rare)
  • 2-3 days: delayed hepatotoxicity (rare)
  • 1-3 days after hepatotoxicity: hemolysis and methemoglobinaemia

Immunohaemolytic, e.g. Paxillus spp

  • <3h: GI symptoms
  • days: hemolytic anemia, immune-complex nephritis and renal failure

Pneumonic, e.g. inhalation of dried Lycoperdonosis spores

  • <6h: N&V, rhinitis
  • days: pneumonia


Hepatotoxic, e.g AmanitaGalerina and Lepiota spp

  • hepatotoxic cyclopeptides: amatoxins, phallotoxins and virotoxins
  • 6-24h: GI symptoms
  • 18-36h: transient improvement, asymptomatic transaminitis
  • 2-6d: severe gastroenteritis, hepatic failure and pancreatitis


  • acromelic acids
  • 24-72h onset, with resolution over 8 day sto 5 months: burining pain, redness and sweeling of hands and feet, exacerbated by heat and cold


Nephrotoxic, e.g. Cortinarius  and A. smithiana spp

  • orellanine-mediated
  • 24-36h: geadache, GI symptoms, flank pain progressing to interstitial nephritis and renal failure

Rhabdomyolysis, e.g. tricholoma  and  Russula  spp

  • onset 24-72h: fatigue, myaligias, muscle weakness and myocarditis (very rare)


  • guided by clinical assessment
  • check LFTs and renal function first if GI symptoms present >6 hours after exposure
  • consider: FBC, UEC, CMP, LFTs, coags, CK, glucose, ECG, blood gas and lactate
  • mycologist examination of mushroom samples



  • rarely necessary
  • life-threats include:
    — gastroenteritis and hypovolemic shock
    — seizures or coma
    — cholinergic crisis

Supportive care and monitoring, may include:

  • neurological observations for seizures, coma and paralysis
  • delirium management
  • glucose monitoring
  • cardiac monitoring
  • rehydration and antiemetics
  • monitor LFTs for 48 hours if suspected cyclopeptide hepatotoxin


  • activated charcoal 50g (1g/kg in children) if onset of GI symptoms occurs >6 hours post-ingestion

Enhanced elimination

  • consider multi-dose activated charcoal if suspected cyclopeptide hepatoxicity as alpha-amantin undergoes enterohepatic circulation


  • cyclopeptide hepatoxicity (e.g. GI symptoms onset >6 hours or increasing transaminases)
    — N-acetylcysteine
    — penicilin 1 MU/kg/day
    — silibinin 5 mg/kg IB over 1 hour then 20 mg/kg/day for up to 3 days
  • cholinergic syndrome — atropine
  • seizures due to Gyromitra  mushrooms — pyridoxine (similar management to isonizid toxicity)


  • discharge home if risk assessment does not predict severe toxicity and:
    — asymptomatic, or
    — early onset GI symptoms are resolving and patient is clinically well (check LFTs and renal function first if lasts >6 hours)
  • observe in hospital:
    — significant symptoms
    — risk assessment predicts potential for severe toxicity
  • admit to HDU/ ICU:
    — coma or CNS dysfunction
    — liver or renal failure (may require transfer to a specialist center)

References and Links

  • Bedry R, Baudrimont I, Deffieux G, Creppy EE, Pomies JP, Ragnaud JM, Dupon M, Neau D, Gabinski C, De Witte S, Chapalain JC, Godeau P, Beylot J. Wild-mushroom intoxication as a cause of rhabdomyolysis. N Engl J Med. 2001 Sep 13;345(11):798-802. PMID: 11556299.
  • Diaz JH. Syndromic diagnosis and management of confirmed mushroom poisonings. Crit Care Med. 2005 Feb;33(2):427-36. PMID: 15699849.
  • Lima AD, Costa Fortes R, Carvalho Garbi Novaes MR, Percário S. Poisonous mushrooms: a review of the most common intoxications. Nutr Hosp. 2012 Mar-Apr;27(2):402-8. PMID: 22732961.
  • Roberts DM, Hall MJ, Falkland MM, Strasser SI, Buckley NA. Amanita phalloides poisoning and treatment with silibinin in the Australian Capital Territory and New South Wales. Med J Aust. 2013 Jan 21;198(1):43-7. PMID: 23330770.

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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