Mushroom toxicity


Clinically broken into two main categories:

  1. Early-Onset Poisoning (toxicity begins within 2hr of ingestion)
    • Clinical course is usually benign
    • Comprises majority of mushroom-induced intoxications
  2. Late-Onset Poisoning (toxicity begins 6hr after ingestion)
    • Clinical course is often serious/ possibly fatal
    • Amanita species causes 95% of deaths
      • Most frequent species: A. phalloides, bisporigera, magnivelaris, ocreata, verna, virosa[1]
      • Toxin inhibits formation of mRNA and is heat stable

Mushroom Identification

Clinical Features


Depends on the type of mushroom ingested

  • GI
    • Nausea/vomiting/diarrhea
    • Resolves within 24hr
  • CNS[2]
    • Isoxazoles (ibotenic acid and muscimol) - dsyarthria, ataxia, muscle cramps
    • Psilocybin - euphoria, visual hallucinations, agitation, sympathomimetic Sxs
    • Lasts 4-8hrs
  • Muscarinic
    • SLUDGE symptoms
    • Diaphoresis, muscle fasciculations, miosis, bradycardia, bronchorrhea
    • Resolves in 4-12hr
  • Disulfiram-like effect
    • Usually when drinking alcohol
    • Flushing, tachycardia, diaphoresis, hypotension


Four Stages [3] [4]

  1. Latent (symptom free, up to 24 hours)
  2. Symptomatic (GI distress)
  3. Convalescent (feel better, but LFT's increasing)
  4. Fulminant (day 2-4)

Differential Diagnosis

Mushroom toxicity by Type

Mushroom Toxin Pathologic Effect
Amanita Amatoxin Hepatotoxicity
Coprine Disulfiram-like
Crotinarius Orellanine Delayed renal failure
Gyromitra Gyromitrin Seizures
Ibotenic Acid Anticholinergic
Muscarine Cholinergic
Orellanin Nephrotoxicity
Psilocybin Hallucinations

SLUDGE Syndrome

Acute hepatitis




  • Hypoglycemia is common cause of death and needs close monitoring



  • GI predominant symptoms:
    • Activated charcoal 0.5-1gm/kg
    • Do not give antidiarrheal meds
  • CNS predominant symptoms:
    • Place in dark, quiet room
    • Benzos may be given to patients who are agitated
    • Consider pyridoxine for refractory seizures, especially if suspecting gyromitra[5]
  • Muscarinic predominant symptoms:
    • Consider atropine for severe symptoms; 0.5-1mg IV for adults; 0.01mg/kg IV for peds


Consider Amatoxin-specific treatments:

  • Activated charcoal
  • N-Acetylcysteine (NAC): 150 mg/kg over one hour, 50 mg/kg over 4 hours, 100 mg/kg over 16 hours
  • Call poison control, consider:
    • Penicillin G
    • Silibinin dihemisuccinate
    • Cimetidine
    • Vitamin C



  • Discharge once symptoms have subsided


  • Admit


  1. Enjalbert F et al. Treatment of Amatoxin Poisoning: 20 year retrospective analysis. J tox Clin Tox 2002 40(6):715-767.
  2. Rolston-Cregler L et al. Hallucinogenic Mushroom Toxicity. Apr 08, 2015.
  3. Brayer AF, Froula L. Mushroom poisoning. In: Tintinalli JE, Stapczynski J, Ma O, Yealy DM, Meckler GD, Cline DM, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill; 2016:(Ch) 219.
  4. Shih RD. Plants, mushrooms and herbal medications. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:(Ch) 164.
  5. Berger KJ, Guss DA. Mycotoxins revisited: Part II. J Emerg Med. 2005;28(2):175.