Can Dogs Eat Mushrooms?

This is a loaded question; common store-bought mushrooms are fine for your dog to eat. Unfortunately, wild mushrooms have a risk of being toxic to both people and dogs. Extreme caution should be taken to keep your dog from eating wild mushrooms.

Dogs can eat common store-bought mushrooms, but be cautious to avoid preparations that involve heavy amounts of oil, butter, and garlic. Preparations with oil and butter can cause pancreatitis or inflammation of the pancreas. Heavy sauces can also cause gastrointestinal upset, including vomiting and diarrhea. Garlic can be toxic for dogs, so recipes with garlic should be also avoided.

In addition to pancreatitis and gastrointestinal upset, mushrooms can be a choking hazard if not chopped into small pieces. Raw or cooked preparations of commercial mushrooms are fine as long as caution is taken with the preparation of sauces and size of the pieces.

Wild mushrooms are much more dangerous to dogs and people. Mushroom toxicity is commonly seen when dogs eat wild mushrooms during off-leash hiking or backyard play.

Here’s a breakdown of clinical signs related to wild mushroom toxicity.

Neurotoxins

Mushrooms that cause neurotoxin poisoning present symptoms like:

• Seizures
• Tremoring
• Weakness
• Ataxia (wobbliness)

The toxins that have been known to cause neurological signs if ingested include:

• Psilocybin and psilocin. These compounds have been found in “magic” mushrooms and are used as recreational drugs. Dogs may ingest them if found in the household, since they are not commonly found in the wild.
• Hydrazine or Monomethylhydrazine. This toxic compound is found in the Gyromitra species of mushrooms, also known as false morels. Ingestion of these mushrooms commonly causes neurological and gastrointestinal signs, but can also cause hemolysis (break down) of red blood cells and kidney and liver injuries.
• Isoxazole derivatives. Isoxazole derivatives are the toxic compounds found in the Amanita species of mushrooms, the derivatives of which are ibotenic acid and muscimol. These mushrooms can cause neurological signs, in addition to gastrointestinal signs like vomiting and diarrhea.

Hepatotoxins

Hepatotoxins are toxic compounds that cause liver injury. These mushrooms will often cause acute liver failure, as well as:

• Vomiting
• Diarrhea
• Coagulation abnormalities
• Jaundice
• Lethargy/weakness
• Dehydration

Mushroom-related fatalities are commonly caused by hepatotoxic mushrooms in dogs and humans. The most common mushroom species associated with liver injuries are Amanita, Galerina, and Lepiota. Amanita phalloides (the death cap mushroom) accounts for more than 50% of mushroom fatalities in people and the most fatal cases in dogs.

The toxic cyclopeptides that cause the liver injuries are:

• Amatoxins
• Phallotoxins
• Virotoxins

Nephrotoxins

Nephrotoxic mushrooms contain toxic compounds that cause injuries to the kidneys and acute kidney failure.

Clinical signs seen with nephrotoxic mushroom poisoning include:

• Vomiting
• Nausea
• Increased drinking
• Increased urination
• Lethargy

Cortinarius species are a type of mushroom found in Japan and Europe. The toxic chemicals in this type of mushroom are orelline and orellanine. Unfortunately, these compounds can cause severe renal injuries, typically requiring kidney transplants for sufferers. No unintentional poisoning in dogs has been documented with this type of mushroom.

Gastrointestinal Toxins

Almost all toxic mushrooms can cause gastrointestinal upset, in addition to other organ injuries such as liver, kidney, and neurological clinical symptoms.

The following mushroom species have been found to have gastrointestinal irritants, but the pathophysiology or toxic compound hasn’t been isolated yet:

• Agaricus
• Boletus
• Chlorophyllum
• Entoloma
• Gomphus
• Hebeloma
• Lactarius
• Naematoloma
• Omphalotus
• Paxillus
• Ramaria
• Rhodophyllus
• Russula
• Scleroderma
• Tricholoma

Miscellaneous Toxins

There are a few mushroom toxicities that don’t quite fit into the categories outlined above.

Muscarine

Muscarine is a toxic compound that is found in Inocybe, Clitocybe, Panaeolus, Gymnopilus, Boletus, Hebeloma, Mycena and Omphalotus species of mushrooms. This compound causes clinical signs that are described as SLUD (salivation, lacrimation (excessive tear production), urination, and defecation).

Coprine

Coprine is the toxic compound found in the Coprinus atramentarius (ink cap) mushroom. This toxicity is not seen in veterinary patients, as it is only seen if this mushroom is consumed in a close time frame with alcohol.

What Should I Do if My Dog Eats a Toxic Mushroom?

First of all, stop your dog from consuming any more of the mushroom in question. Secondly, if possible, take a sample of the mushroom that was ingested, since this can help identify the mushroom and assist your veterinarian in treating your dog. The sample can be taken from the actual fungi itself or by documenting the mushroom with photos that can be used for identification.

If your dog consumes a potentially toxic wild mushroom, they should be brought to a veterinary hospital to induce emesis, in hopes of them vomiting up the ingested toxin. Clinical signs can vary depending on the species ingested, and they can occur anywhere between 30 minutes to 10-12 hours after ingestion. Therefore, initiating treatment immediately is important, instead of waiting to see if clinical signs develop.

Your veterinarian will most likely reach out to a pet poison specialist to help identify the mushroom and guide treatment based on the suspected mushroom species. A local mycologist may also be helpful in identifying the toxic mushroom.

Treatment and recovery from toxic mushroom ingestion is largely based on the severity of clinical signs. Some toxicities will be mild and respond with supportive care. Other toxicities, especially those that affect the liver, can be fatal even with aggressive treatment.