My Dog Ate a Mushroom. Now What?

Dogs are naturally curious creatures and love to explore the world with their nose and mouth. Being natural scavengers, this curiosity can lead to trouble when they ingest things they shouldn’t.

There are thousands of species of mushrooms throughout the U.S. Mushrooms thrive in warm, humid climates and can be found almost anywhere, including your backyard.

When determining which mushrooms to avoid with your dog, pay close attention to areas with dead organic matter, such as compost or rotting wood.

While most mushrooms are considered non-toxic, some can cause a wide variety of symptoms. Any wild mushroom ingestion by your dog should be treated as toxic unless a veterinarian or trained poison specialist identifies the mushroom as non-toxic.

If your dog ingests a wild mushroom, call the Pet Poison Helpline at 1-855-764-7661 or your veterinarian to help determine next steps.

Are Mushrooms Toxic to Dogs?

Mushrooms found at grocery stores and prepared for human consumption are not considered toxic to dogs. However, while grocery store mushrooms themselves aren’t harmful, human foods cooked with oils, seasonings, or certain other ingredients should never be fed to your dog.

Most wild mushrooms are not toxic but some can be highly dangerous—and even deadly—to dogs.  

Mushroom poisoning in dogs affects different organ systems, depending on the type of mushroom ingested. The gastrointestinal and nervous systems are commonly affected and some mushrooms can cause liver or kidney damage. Signs of poisoning can appear within 15–20 minutes or may be delayed up to a day.

Poisonous Mushrooms Toxic to Dogs

Liver and Kidney Toxic Mushrooms

Cyclopeptide-containing mushrooms produce toxic peptides that are responsible for most mushroom-related deaths in humans each year. These mushrooms, often found outdoors (including in backyards), are just as dangerous to our pups.

The main groups of cyclopeptide-containing mushrooms include:

• Amanita

• Galerina

• Lepiota

These mushrooms are found throughout North America, particularly in areas like the San Francisco Bay area and British Columbia, as well as the eastern U.S. from Maine to Maryland. They are generally found near trees as opposed to open yards or fields. Cyclopeptide-containing mushrooms are the most toxic to both dogs and humans. If you think your dog has ingested one, contact your veterinarian immediately.

Early symptoms of mushroom toxicity in dogs may include:

• Vomiting and diarrhea (with or without blood)
• Lethargy
• Abdominal pain

24–48 hours after ingestion a dog may experience:

• Liver and kidney damage

Unfortunately, these mushrooms can vary in appearance, which is why humans often mistake them for edible varieties. If a dog ingests one of these mushrooms, recovery may take up to three weeks. Tragically, death may occur within one to five days.

Mushrooms Causing Stomach-Related Issues

The following mushrooms cause the most stomach-related issues in dogs and can be found throughout the U.S. The most common types include:

• Agaricus

• Boletus

• Chlorophyllum

• Entoloma

• Lactarius

• Omphalotus

• Panaeolus foenisecii

• Rhodophyllus

• Scleroderma

The most common symptoms linked to mushroom toxicity in dogs include:

• Vomiting

• Diarrhea

• Loss of appetite

• Abdominal cramping

Inocybe and Clitocybe are muscarinic mushrooms (those containing compounds that affect the nervous system by mimicking acetylcholine, a neurotransmitter). These mushrooms cause gastrointestinal distress along with additional symptoms, such as:

• Increased tear production

• Excessive drooling

• Low heart rate

Neurotoxic Mushrooms

Some mushrooms contain toxins that specifically target the nervous system, leading to various neurological symptoms. The effects depend on the type of mushroom ingested and the specific toxins they produce.

Hallucinogenic Mushrooms

Psilocybe, Panaeolus (excluding P. foenisecii), Conocybe, and Gymnopilus. These mushrooms contain psilocybin and psilocin, compounds that affect the brain and cause hallucinations. They are most commonly found in the Northwest and Southeast regions of the U.S.

If your dog ingests a hallucinogenic mushroom, neurological symptoms may include:

• Weakness

• Vocalization

• Aggression

• Ataxia (wobbly walk)

• Tremors

Hydrazine toxins. Gyromitra and Helvella mushrooms contain hydrazine toxins, which can disrupt the central nervous system and may also cause gastrointestinal issues. Found in spring throughout North America, they are typically located near or under conifers and aspen trees.

If your dog ingests one of these mushrooms, symptoms may include:

• Vomiting and diarrhea

• Lethargy

• Tremors

• Seizures

• Liver damage (rare)

Isoxazole toxins. Amanita pantherina and Amanita muscaria. These mushrooms contain isoxazole compounds (ibotenic acid and muscimol) that act as neurotoxins. They disrupt normal brain function by mimicking or blocking neurotransmitters. These mushrooms, with their distinctive fishy odor, are found in forests in the summer and fall, most commonly in the Pacific Northwest.

Symptoms associated with these mushrooms may include:

• Seizures
• Paralysis
• Pinpoint pupils (abnormally small pupils)
• A deep, coma-like sleep

My Dog Ate a Mushroom. What Should I Do?

Identifying the type of mushroom your dog has ingested is crucial when determining the next steps. However, if your dog is already showing signs of illness, the safest thing to do is to seek immediate veterinary care before trying to identify the mushroom.

It’s recommended to save any parts of the mushroom found in your dog’s mouth (even if chewed) or in their vomit for identification purposes.

If possible, collect samples from the environment where the mushroom was ingested. Place the samples in wax paper or on a paper towel, then put them in a paper bag labeled “Do not eat.” 

Since several species of mushrooms can grow within proximity to each other, having actual pieces from your dog’s mouth or vomit is very helpful. Call your veterinarian or Pet Poison Helpline at 1-855-764-7661 for guidance on next steps.

Treatment of Mushroom Poisoning in Dogs

The first goal is to limit absorption of the mushroom in your dog’s system. This may involve your vet inducing vomiting at the vet clinic and administering activated charcoal to help absorb the toxin.

Important: Induced vomiting should never be done at home or without the guidance of a veterinarian, as it can sometimes cause more harm, such as aspiration pneumonia.  

Treatment for mushroom poisoning in a dog is tailored to the type of mushroom ingested and may include:

• Anti-nausea and anti-diarrhea medication (Cerenia or ondansetron may be prescribed)

• Anti-convulsants or muscle relaxants to address neurologic symptoms  

• Hydration support, particularly if the mushroom causes dehydration or potential kidney damage

Sometimes, it’s impossible to identify the mushroom your dog ingested. In those instances, your veterinarian may elect to induce vomiting, perform blood work, and/or monitor your dog for several hours after ingestion to make sure severe clinical signs do not develop.

Prevention of Mushroom Poisoning in Dogs

As a prevention, keep a close eye on your dog while in they’re in the yard or out on a hike, especially after a rainy day or in areas with dead trees. Mushrooms can pop up very quickly, so it’s important to check for them early and often.

If your dog has access to your backyard, regularly remove any mushrooms that sprout during the spring and summer months. If you want to keep your dog out of certain areas in the yard, consider investing in an outdoor exercise playpen. This can help keep your dog safe while allowing them the freedom to play.