Deadly Poisonous Mushrooms: Visual Identification Guide (2025)

Mushroom Poisoning Statistics & Overview

According to the North American Mycological Association (NAMA) and CDC data, mushroom poisoning remains a serious public health concern in the United States and Canada:

• 7,000+ cases of mushroom poisoning reported annually to U.S. poison control centers
• 3-5 deaths per year in North America from mushroom poisoning (NAMA data 2015-2025)
• 90% of mushroom-related deaths are caused by Amanita species (Death Cap and Destroying Angels)
• 60% of victims are immigrants who mistake toxic species for edible mushrooms from their home countries
• 25% of serious poisonings involve experienced foragers who made identification errors

Categories of Mushroom Toxicity

The North American Mycological Association classifies mushroom poisonings into categories based on symptom onset and toxin type:

Category 1 - Deadly (Delayed Symptoms 6+ Hours):

• Amatoxins (Death Cap, Destroying Angels, Deadly Galerina) - Liver and kidney failure, often fatal
• Orellanine (Deadly Webcap) - Kidney failure, symptoms delayed 2-14 days
• Gyromitrin (False Morels) - Liver damage, potentially fatal

Category 2 - Serious (Symptoms within 6 Hours):

• Muscarine (some Inocybe, Clitocybe) - Sweating, salivation, respiratory distress
• Coprine (Inky Caps with alcohol) - Alcohol intolerance reaction

Category 3 - Moderate (Gastrointestinal Distress):

• Various species causing nausea, vomiting, diarrhea within 1-3 hours

Death Cap (Amanita phalloides) - The World's Deadliest Mushroom

Critical Identification Features

Cap:

• 5-15 cm diameter (2-6 inches)
• Color ranges from pale yellow-green to olive to greenish-brown
• Smooth, hairless surface (may have white veil patches when young)
• Often darker in center, paler toward margins
• Sticky when wet, shiny when dry

Gills:

• White, always white (never discoloring)
• Free from stem (do not attach to stem)
• Crowded, closely spaced

Stem:

• White to pale yellow-green
• 5-15 cm tall (2-6 inches)
• Prominent white skirt-like ring (annulus) on upper stem
• CRITICAL: Large white sac-like volva at base (cup that may be buried in soil)

Spore Print: White

Habitat:

• Mycorrhizal with oak, chestnut, pine in western regions
• Originally European, now established in California, Pacific Northwest, British Columbia
• Spreading to eastern North America through landscape trees
• Late summer through fall fruiting
• Often found in urban parks and landscapes with imported oak trees

Toxin Mechanism: Amatoxins

Death Caps contain two primary toxin groups:

Alpha-amanitin (amatoxins):

• Blocks RNA polymerase II enzyme, preventing protein synthesis
• Primarily damages liver cells, also affects kidneys and intestines
• Causes cell death in rapidly dividing tissues
• NOT destroyed by cooking, freezing, or drying
• Lethal dose: 0.1 mg/kg body weight (about 10mg for an adult)

Phallotoxins:

• Damage intestinal lining
• Contribute to initial gastrointestinal symptoms
• Less toxic than amatoxins but cause severe distress

Symptom Timeline (Amatoxin Syndrome)

Phase 1: Latent Period (6-24 hours post-ingestion)

• No symptoms - you feel completely normal
• Toxins are actively damaging liver and kidneys
• THIS IS THE MOST DANGEROUS PHASE - people delay seeking help

Phase 2: Gastrointestinal Phase (24-48 hours)

• Sudden onset of severe abdominal cramping
• Violent vomiting (may be bloody)
• Profuse watery or bloody diarrhea
• Severe dehydration
• Weakness and dizziness

Phase 3: False Recovery (48-72 hours)

• GI symptoms may improve dramatically
• Patient feels better and may refuse hospitalization
• WARNING: This is deceptive - liver damage is worsening
• Lab tests show elevated liver enzymes

Phase 4: Organ Failure (3-7 days)

• Liver failure: jaundice, confusion, bleeding disorders
• Kidney failure: decreased urination, fluid retention
• Hepatic encephalopathy (brain dysfunction from liver failure)
• Coagulopathy (blood clotting disorders)
• Multiple organ system failure

Outcome: Death in 10-20% of cases, often within 7-10 days. Survivors may require liver transplant. Even with transplant, full recovery is not guaranteed.

Treatment Protocol

Standard medical treatment (administered by physicians):

1. Activated Charcoal: If within 1-2 hours of ingestion, reduces toxin absorption
2. Gastric Lavage: Stomach pumping in early stages
3. Aggressive IV Hydration: Prevents dehydration, supports kidney function
4. Silibinin (Milk Thistle Extract): IV administration may reduce liver damage (most effective if given within 48 hours)
5. Penicillin G: High-dose IV may interrupt toxin uptake by liver cells
6. N-acetylcysteine: Antioxidant support for liver
7. Liver Transplant: May be necessary in severe cases
8. Continuous Monitoring: Daily liver and kidney function tests

Prognosis factors: Early treatment, amount consumed, patient health status. Children and elderly are at higher risk of fatal outcomes.

Destroying Angels (Amanita Species)

Critical Identification Features

Cap:

• Pure white (all species)
• 5-12 cm diameter
• Convex to flat with age
• Smooth or slightly sticky when wet
• May have veil remnants on cap surface when young

Gills:

• Pure white, free from stem
• Crowded
• Remain white at all stages (never discoloring)

Stem:

• White, 8-20 cm tall
• Prominent white ring (annulus) on upper stem
• CRITICAL: White sac-like volva at base (may be underground)
• Often has shaggy or scaly texture below ring

Spore Print: White

Habitat:

• Widespread across North America
• Amanita bisporigera (Eastern North America) - most common
• Amanita ocreata (Pacific Coast) - especially deadly
• Mixed hardwood and conifer forests
• Mycorrhizal associations with various trees
• Summer through fall

Species-Specific Notes

Amanita bisporigera (Eastern Destroying Angel):

• Most common in eastern United States
• Distinguishing feature: produces only 2 spores per basidium (visible only microscopically)
• Very fragile - often breaks apart when handled

Amanita ocreata (Western Destroying Angel):

• Pacific Coast specialist
• Particularly toxic strain of amatoxins
• Associated with oak, pine, madrone
• Responsible for most West Coast mushroom fatalities

Amanita virosa & A. verna (European Species):

• Occasionally found in North America
• Identical toxicity to North American species

Toxins & Symptoms

Destroying Angels contain the same amatoxins as Death Cap. Symptoms follow identical timeline:

• 6-24 hour latent period (no symptoms)
• Severe gastrointestinal distress (24-48 hours)
• False recovery period (48-72 hours)
• Liver and kidney failure (3-7 days)
• Death or liver transplant required

Treatment protocol identical to Death Cap poisoning (see above).

False Morels (Gyromitra Species)

Critical Identification Features

Gyromitra esculenta (Common False Morel):

• Cap: Brain-like, irregularly lobed and folded (NOT honeycomb pitted like true morels)
• Reddish-brown to dark brown color
• 5-10 cm diameter, wrinkled appearance
• Folds are irregular, wavy, gyrus-like (brain-like)

Interior Structure (CRITICAL DIFFERENCE):

• False Morels: NOT hollow - filled with white cottony/chambered tissue
• True Morels: Completely hollow from top to bottom
• ALWAYS cut suspected morels in half lengthwise to verify hollow interior

Stem:

• White to cream colored
• Short and thick
• May be grooved or wrinkled
• Contains chambers (not hollow)

Habitat:

• Spring (April-June), same season as true morels
• Sandy soils, disturbed ground
• Near conifers (especially pine and spruce)
• Sometimes on old logging roads, burned areas
• Northern temperate regions

Other Gyromitra Species

Gyromitra caroliniana (Carolina False Morel):

• Similar brain-like cap structure
• Reddish-brown color
• More common in southern states
• Contains same toxins

Gyromitra infula (Hooded False Morel):

• More saddle-shaped than brain-like
• Brown to reddish-brown
• Fall fruiting (unlike spring morels)
• Potentially toxic

Toxin: Gyromitrin (Monomethylhydrazine)

Mechanism:

• Gyromitrin metabolizes into monomethylhydrazine (rocket fuel component)
• Damages liver cells and red blood cells
• Depletes glutathione (antioxidant), causing cellular damage
• Neurotoxic effects possible

Toxicity Variability:

• Toxin levels vary widely between individual mushrooms and locations
• Some people can eat them with no effects; others get severely poisoned from small amounts
• Repeated exposure may cause cumulative toxicity
• Parboiling and discarding water reduces but does NOT eliminate toxins
• Children are at higher risk of severe poisoning

Symptoms (Onset 6-12 Hours)

Mild to Moderate Poisoning:

• Nausea and vomiting
• Abdominal cramping
• Diarrhea
• Headache and dizziness
• Fatigue

Severe Poisoning:

• Liver damage (elevated liver enzymes)
• Jaundice
• Seizures (rare but documented)
• Hemolysis (destruction of red blood cells)
• Methemoglobinemia (reduced oxygen-carrying capacity of blood)
• Kidney damage
• Death in 2-4% of serious cases

Treatment

1. Immediate medical attention if any symptoms appear
2. Activated charcoal if within hours of ingestion
3. IV hydration to support kidney function
4. Pyridoxine (Vitamin B6): High doses may reduce seizure risk
5. Methylene blue: For methemoglobinemia if present
6. Liver function monitoring for several days
7. Supportive care for symptoms

Deadly Galerina (Galerina marginata)

Critical Identification Features

Cap:

• Small: 0.5-4 cm diameter (1/4 to 1.5 inches)
• Honey-brown to yellowish-brown when moist
• Dries to pale tan or buff color
• Hygrophanous (changes color as it dries, often with darker center)
• Smooth surface
• Convex to broadly convex or flat
• Margin often striate (lined) when moist

Gills:

• Attached to stem (adnate to slightly decurrent)
• Close to crowded spacing
• Pale brown to rusty brown with age

Stem:

• 2-6 cm tall, very thin (1-4 mm thick)
• Pale brown to yellowish above
• Darker brown below
• Fragile ring zone on upper stem (often disappears with age)
• Slightly fibrous or silky appearance
• No volva at base

Spore Print: Rusty brown

Habitat:

• On decaying conifer wood (stumps, logs, buried wood)
• Occasionally on hardwood
• Often in large clusters
• Spring through fall (peak late summer/fall)
• Widespread throughout North America
• Common in forests, parks, woodchip mulch

Toxin & Symptoms

Deadly Galerina contains the same amatoxins as Death Cap and Destroying Angels (primarily alpha-amanitin).

Symptom timeline identical to Amanita poisoning:

• 6-24 hour latent period (no symptoms)
• Severe gastrointestinal phase (24-48 hours)
• False recovery (48-72 hours)
• Liver and kidney failure (3-7 days)
• High mortality rate without liver transplant

Treatment: Identical to Death Cap poisoning protocol (IV silibinin, penicillin G, aggressive supportive care, possible liver transplant).

Deadly Webcap (Cortinarius rubellus)

Critical Identification Features

Cap:

• 3-8 cm diameter
• Orange-brown to rusty brown color
• Dry surface with fine scales or fibrous texture
• Conical to bell-shaped, becoming flatter with age
• Often has small pointed umbo (central bump)

Gills:

• Widely spaced (distant)
• Rusty brown color
• Broad and thick
• Attached to stem

Stem:

• 5-10 cm tall
• Yellow to orange-brown color
• Fibrous texture with faint bands/zones
• Young specimens have cortina (cobweb-like partial veil) connecting cap edge to stem
• Cortina leaves rusty brown zone on stem as spores mature

Spore Print: Rusty brown

Habitat:

• Mycorrhizal with conifers (especially spruce and pine)
• Acidic soils
• Northern forests
• More common in Europe, but found in Pacific Northwest
• Late summer to fall

Related Deadly Species

Cortinarius orellanus (Fool's Webcap):

• Nearly identical toxicity
• Orange to tawny-orange cap
• More common in Europe, rare in North America
• Mycorrhizal with oak and beech

Note: Over 2,000 Cortinarius species exist worldwide. Many are difficult to identify. Several species beyond C. rubellus and C. orellanus may contain orellanine or similar nephrotoxins. Avoid eating any Cortinarius species unless you are an expert mycologist.

Toxin: Orellanine

Mechanism:

• Orellanine and related compounds (orelline, orellinine)
• Bipyridine compounds that cause oxidative damage
• Selectively toxic to kidney tubule cells
• Causes acute tubular necrosis and interstitial nephritis
• Damage is often irreversible
• NOT destroyed by cooking or drying

Symptoms: Delayed Kidney Failure

Phase 1: Extremely Long Latent Period (2-14 days, sometimes up to 3 weeks)

• Absolutely no symptoms for days to weeks
• Victim may not remember eating the mushrooms
• Kidney damage is progressing silently
• This extreme delay makes treatment very difficult

Phase 2: Initial Symptoms (2-3 weeks post-ingestion)

• Extreme thirst and dry mouth
• Excessive urination at first
• Nausea and vomiting
• Headache
• Muscle pain and weakness
• Chills and feeling cold
• Loss of appetite

Phase 3: Kidney Failure (Weeks to Months)

• Decreased urination or complete kidney shutdown
• Fluid retention and edema (swelling)
• High blood pressure
• Metabolic acidosis
• Electrolyte imbalances
• Uremia (waste products accumulating in blood)
• Kidney biopsy shows tubular necrosis

Long-term Outcome:

• Death in 10-15% of cases from kidney failure
• 30-50% require permanent dialysis
• Some recover partial kidney function over months to years
• Complete recovery is rare
• Kidney transplant may be necessary

Treatment

Medical interventions:

1. Hemodialysis: Removes toxins and waste products, supports kidney function
2. Hemoperfusion: Blood filtering through charcoal may help in early stages
3. Corticosteroids: May reduce inflammatory kidney damage (controversial efficacy)
4. Fluid and electrolyte management: Careful balance to avoid worsening kidney damage
5. Blood pressure control: Prevent further kidney damage from hypertension
6. Plasmapheresis: Plasma exchange (limited evidence of benefit)
7. Long-term dialysis: May be permanent
8. Kidney transplant: For irreversible failure

General Poisoning Symptoms & Timeline Guide

Understanding when symptoms appear is critical for determining poisoning severity and treatment urgency:

Rapid Onset Symptoms (Within 1-3 Hours)

Usually indicates gastrointestinal irritants (less dangerous but still requiring medical attention):

• Nausea and vomiting
• Abdominal cramping
• Diarrhea
• Generally not life-threatening
• Recovery within 24-48 hours with supportive care

Examples: Jack O'Lanterns, Green Gills, various Boletes

Delayed Onset Symptoms (6-24 Hours)

ASSUME DEADLY POISONING - SEEK EMERGENCY CARE IMMEDIATELY

• Amatoxin poisoning (Death Cap, Destroying Angels, Deadly Galerina)
• Gyromitrin poisoning (False Morels)
• Initial GI symptoms followed by liver/kidney failure
• Often fatal without aggressive treatment

Very Delayed Onset (Days to Weeks)

Orellanine poisoning (Deadly Webcaps):

• 2-14+ days before any symptoms
• Progressive kidney failure
• Often irreversible damage
• May require permanent dialysis

Other Symptom Patterns

Muscarine poisoning (some Inocybe, Clitocybe):

• Onset: 15 minutes to 2 hours
• SLUDGE syndrome: Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis
• Excessive sweating
• Respiratory distress in severe cases
• Treated with atropine

Ibotenic acid/muscimol (Amanita muscaria, A. pantherina):

• Onset: 30 minutes to 2 hours
• Confusion, delirium
• Drowsiness alternating with excitement
• Visual distortions
• Rarely fatal but requires medical supervision

Emergency Treatment Protocols

Immediate Actions (Before Emergency Services Arrive)

1. Preserve Evidence:
   • Save any leftover mushrooms (refrigerate in paper bag)
   • Save cooking scraps, peelings, or stems
   • Take photos of mushrooms if possible
   • Note location where mushrooms were collected
2. Do NOT Induce Vomiting unless instructed by Poison Control (1-800-222-1222)
3. Do NOT Give Food or Drink unless instructed by medical professionals
4. Monitor Vital Signs: Breathing, consciousness, pulse
5. Keep Person Calm and Comfortable

Hospital Treatment Overview

Emergency Department Assessment:

• Full history: species description, time of ingestion, amount consumed
• Identification of mushroom species if sample available
• Baseline labs: liver enzymes, kidney function, complete blood count, electrolytes
• Urinalysis

Decontamination (if recent ingestion):

• Activated charcoal within 1-2 hours of ingestion
• Gastric lavage (stomach pumping) in some cases
• Multiple doses of activated charcoal for amatoxin poisoning

Specific Antidotes/Treatments:

• Silibinin (IV): For amatoxin poisoning - most effective within 48 hours
• Penicillin G (high-dose IV): For amatoxin poisoning
• Atropine: For muscarine poisoning
• Pyridoxine (Vitamin B6): For gyromitrin poisoning
• Methylene blue: For methemoglobinemia from gyromitrin

Supportive Care:

• Aggressive IV hydration
• Electrolyte balance
• Anti-nausea medications
• Monitoring liver and kidney function daily
• Blood product transfusions if coagulopathy develops

Advanced Interventions (if needed):

• Hemodialysis for kidney support
• Liver transplant evaluation for fulminant hepatic failure
• ICU admission for severe cases
• Continuous monitoring of organ function

Poison Control Centers

United States: 1-800-222-1222 (connects to local poison control center)

Available 24/7 for free, confidential medical advice

When calling, have ready:

• Patient age and weight
• Mushroom description (color, size, where found)
• Time of ingestion
• Amount consumed
• Current symptoms

Prevention: How to Stay Safe

Essential Safety Practices

1. Use Multiple Identification Methods

• Cross-reference multiple field guides specific to your region
• Use mobile apps like Mushroom Tracker for preliminary identification
• Take spore prints (critical for many species)
• Join local mycological society forays with experts
• Get expert verification before eating any mushroom

2. Learn Deadly Species First

• Before learning edibles, memorize deadly mushrooms in your region
• Know their key identifying features and lookalikes
• Understand their habitats and fruiting seasons
• This "avoidance strategy" is as important as identification

3. Understand Critical Features

• Volva (cup at stem base): Present in deadly Amanitas - always dig up base to check
• Ring on stem: Combined with volva = deadly Amanita
• Spore print color: Critical for identification - always verify
• Habitat: On wood, soil, specific tree associations
• Interior structure: Hollow vs. solid vs. chambered

4. Start with "Foolproof" Species

• Morels (verify hollow interior, honeycomb cap)
• Chicken of the Woods (unmistakable bright orange shelves)
• Lion's Mane (white icicle-like spines, no lookalikes)
• Giant Puffballs (cut in half to verify no gills/stem inside)

5. Avoid High-Risk Species Groups

• Little Brown Mushrooms (LBMs): Too difficult for beginners, includes Deadly Galerina
• All-white mushrooms with gills: Impossible to distinguish from Destroying Angels without expertise
• Any Amanita species: Even "edible" Amanitas are risky due to lookalike dangers
• All Cortinarius species: Too difficult to identify, some contain deadly orellanine

6. Practice Conservative Mushroom Handling

• Keep different species separate (use paper bags, label each)
• Never mix known and unknown mushrooms
• Wash hands after handling unknown mushrooms
• Store samples for identification, even after cooking
• Take multiple photos from different angles before harvesting

7. Test Your Tolerance

• Even with confirmed edible species, try only small amounts first
• Cook thoroughly (most mushrooms are toxic when raw)
• Wait 24-48 hours before eating more
• Some people have allergic reactions to generally edible species

8. Join Mycological Organizations

• North American Mycological Association (NAMA)
• Local mycological societies offer forays with expert identifiers
• Attend mushroom identification workshops
• Build relationships with experienced foragers

Final Critical Reminders

Remember: No meal is worth your life. Mushroom foraging can be a safe and rewarding hobby when practiced with proper education, caution, and respect for the deadly species that exist alongside edible ones. Learn to identify dangerous mushrooms first, master their lookalikes, and always err on the side of caution.

The mushrooms described in this guide cause agonizing, preventable deaths every year. By learning their identification features and understanding their toxicity, you protect yourself and can potentially save others by sharing this critical safety information.

When in doubt, throw it out. Stay safe, and happy foraging.