Toadstools Poisonous to Dogs: Species, Signs and Timing

No, not scientifically. Wikipedia describes 'toadstool' as a word that generally refers to a poisonous mushroom, and notes that the line between edible and poisonous fungi is not clear-cut. 'Mushroom' is not a formal biological category either; both words describe the fleshy fruiting bodies of fungi. The word toadstool first appeared in 14th-century England, as a 'stool' for toads.

For a dog owner the practical point is simple: you cannot tell from the look of a toadstool, or from which word people use for it, whether it will harm your dog. Treat every wild mushroom a dog eats as potentially toxic.

Two lists cover most of what dogs meet: NAMA's list of the mushrooms of greatest concern in dogs (North America) and Vets Now's seven highly poisonous species (UK). Grouped by toxin:

• Liver toxins (amatoxins). Death cap (both lists; Vets Now calls it responsible for the majority of mushroom poisonings globally), destroying angel Amanita virosa (UK) and Amanita bisporigera (U.S.), funeral bell (both), fool's conecap and Lepiota subincarnata (NAMA).
• Kidney toxin. Deadly webcap, Cortinarius rubellus (Vets Now).
• Muscarine. Clitocybe species, including the fool's funnel Clitocybe rivulosa (Vets Now) and the ivory funnel, and Inocybe species (NAMA).
• Ibotenic acid and muscimol. Panther cap (Vets Now) and fly agaric; NAMA says both fly agaric and Amanita pantherinoides are frequently eaten by dogs.
• Earthballs. Scleroderma species, listed by NAMA among the mushrooms of concern for dogs.
• Angel's wings, Pleurocybella porrigens, on the Vets Now list.

NAMA adds that dogs take a special interest in death caps and Inocybe species, quite possibly because of their fishy smell.

Anywhere from minutes to a full day, depending on the toxin, and liver damage shows even later:

• Within 15 to 30 minutes for some mushrooms, and up to 24 hours for others, with evidence of liver and kidney failure taking 2 to 3 days (PetMD).
• Muscarine (Clitocybe, Inocybe): within hours (NAMA).
• Fly agaric and panther cap: a deep, coma-like sleep a few hours after eating; recovery is generally complete about 6 hours later, but can take as long as 72 hours (NAMA).
• Amatoxins (death cap, funeral bell): a delay of 6 to 12 hours or more, then severe gut illness (NAMA). NC State's veterinary hospital describes vomiting and diarrhoea 6 to 12 hours after eating, a deceptive recovery, then liver failure.

This is why a dog that seems normal an hour after eating a mushroom has not been cleared.

PetMD sorts mushroom poisoning in dogs into three patterns:

• Gut: vomiting and diarrhoea, which can lead to significant dehydration and a slowed heart rate.
• Nervous system: stumbling, tremors and seizures.
• Kidney: illness from kidney failure.

Vets Now describes the muscarine signs, drooling, watery eyes, loss of bladder control, diarrhoea, gut cramps and vomiting, which can progress to weakness, collapse and organ failure; the neurotoxic species cause drunken-looking movement, hallucinations, seizures, coma or death. None of these signs has to appear before you call.

There is no specific antidote for mushroom poisoning in dogs (PetMD; Vets Now). Treatment is about getting the toxin out and supporting the organs:

• Inducing vomiting if the dog ate the mushroom within about two hours, or activated charcoal (PetMD). Do not make your dog vomit on your own initiative.
• Bloodwork daily for 72 hours to watch the liver (PetMD).
• For death caps, NC State's veterinary hospital uses a modified Santa Cruz protocol that includes repeated gallbladder drainage to limit recirculation of the toxin.

PetMD describes the outlook with early treatment as very good, though some dogs still die. NC State's clinician calls death cap poisoning nearly 100% fatal without intervention. Bring a specimen of the mushroom in a paper bag, or clear photos, because the treatment plan depends on the toxin.

Among mushrooms, the amatoxin carriers: Amanita, especially the death cap, plus Galerina and Lepiota. PetMD says a single Amanita may contain enough toxin to kill a dog, and NC State reported two dogs dying of death cap poisoning in a single week in May 2025. Because these toxins act slowly, the dog can look well for most of a day while the liver is being damaged.

• Check the yard after rain and remove mushrooms (Firehouse Animal Health Center); the ASPCA suggests walking the yard daily in mushroom season.
• Supervise dogs outdoors in warm, damp weather (NC State).
• On walks, avoid damp areas, use a lead, consider a basket muzzle for a dog that scavenges, and teach a reliable 'drop' or 'leave' (Vets Now).
• Sniffing is not the danger; Firehouse notes toxicity comes from eating. The ASPCA's concern is wild mushrooms, not grocery mushrooms sold for people.

If a dog has eaten a yard mushroom, go straight to dog ate mushroom in yard.