Dogs and Mushrooms: A Potentially Lethal Mix

Donato © Diana Gerba


I remember the sad sinking feeling I experienced last August as I read an email from my friend Diana Gerba.  Seeing her email in my inbox initially prompted excitement- oh goodie, more photos and stories about Donato,  Diana’s adorable Bernese Mountain Dog. My excitement quickly morphed into utter disbelief as Diana described the death of her barely six-month-old pup caused by ingestion of a poisonous mushroom.      

Diana’s heart was broken.  As she wrote in her email,     

A special boy, Donato was a silver tipped puppy, a rarity in our breed. With his tail always wagging, he had boundless enthusiasm for life.  He was a happy little chap and was my joy.  He loved me and I him. We were a team ordained by the stars.      


Diana and Donato © Peter Nystrom

Every region of the country is different in terms of mushroom flora. Where I live in northern California, Amanita phalloides (aka Death Cap) is the most common poisonous species and grows year round particularly in soil surrounding oak trees.  Ingestion of a Death Cap mushroom causes liver failure (in people and in dogs)- makes sense given the liver’s function as the “garbage disposal” of the body. Symptoms typically include vomiting, diarrhea, lethargy, loss of appetite, delayed blood clotting, and neurological abnormalities.  Every year at my busy hospital, we see at least a handful of dogs with liver failure clearly caused by mushroom ingestion.  In spite our very best efforts, the individuals who survive mushroom poisoning are few and far between. Affected people can receive a liver transplant; no such technology available (yet) for dogs.      


To learn more about poisonous mushrooms visit the North American Mycological Association and Bay Area Mycological Society websites.  If you suspect your dog has ingested a mushroom get to your veterinary clinic or the closest emergency care facility immediately (choose whichever is most quickly accessible).  If possible, take along a sample of the mushroom so it can be professionally identified if need be.     


Fortunately, my friend Diana has managed to put a positive spin on the loss of her beloved Donato.  Not only does she have Tesoro, a new little Berner boy in her life, she has made it her personal mission to warn people about the potential hazards of mushroom toxicity in dogs.  She created the attached flyer (see above).  Feel free to download and post it wherever dog loving people congregate.  Diana sent a blast email out just a few days ago after finding a Death Cap mushroom in her yard.   Coincidentally, today I discovered several mushrooms on my property while beginning the task of weeding my garden. They’re gone now, but given our current weather pattern, I’m quite sure there will be more tomorrow.     

What can you do to prevent your dog from ingesting a poisonous mushroom?  Clear any mushrooms from your dog’s immediate surroundings, and be super vigilant on your walks, particularly if you have a pup (youngsters love to put anything and everything in their mouths) or an adult dog who is a known indiscriminate eater.  Learn more about which poisonous mushrooms grow in your area and what they look like.  And please remember, if you see your dog ingest a mushroom- get yourselves to a veterinary hospital as quickly as possible (even if it is after hours). Ingestion of even a nibble of a toxic mushroom is life threatening, and the sooner treatment is started the greater the likelihood of saving your best buddy.     

Are you aware of poisonous mushrooms in your neck of the woods?  If so, please share where you live (city and state) and the name of the mushroom if you happen to know it.     

Best wishes for good health,       

Nancy Kay, DVM
Diplomate, American College of Veterinary Internal Medicine
Author of Speaking for Spot: Be the Advocate Your Dog Needs to Live a Happy, Healthy, Longer Life
Recipient, American Animal Hospital Association Animal Welfare and Humane Ethics Award
Recipient, Dog Writers Association of America Award for Best Blog
Recipient, Eukanuba Canine Health Award
Recipient, AKC Club Publication Excellence Award
Become a Fan of Speaking for Spot on Facebook       

Please visit to read excerpts from Speaking for Spot. There you will also find “Advocacy Aids”- helpful health forms you can download and use for your own dog, and a collection of published articles on advocating for your pet’s health. Speaking for Spot is available at, local bookstores, and your favorite online book seller.      

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9 Comments on “Dogs and Mushrooms: A Potentially Lethal Mix

  1. Pingback: Dogs and wild mushrooms are a dangerous combination |

  2. I live in southeastern PA, (Glenmoore, which is in Chester County) and almost lost a dog to clitocybe dealbata (identified after the fact by the mycologist at the county Penn State Agricultural Extension) in Oct. 2008. He went into respiratory arrest for 2 minutes, luckily that happened a few minutes after I noticed that a vet office we were passing on the way to the 24-hr emergency vet hospital was open (it was 8 am on a Sat.) Banjo was in the hospital for 2 days, I don’t think any of the vets thought he was going to make it, but he’s still with me more than 2 years later with no apparent long-term effects.

    My field (about 1/3 acre) was horse pasture for decades until 1998. I have too many species of wild mushrooms to count, they can appear from March through December.

  3. Wow – I never thought about how dogs might react to mushrooms. We do have a number of poisonous ones that grow all around us here on the OR coast. We’ve been interested in learning to hunt the good ones (like chanterelles) but it’s a little scary unless you can go out with someone who really knows! We don’t have a dog right now, but I’m glad to have this information filed away for the future!

  4. This past October 2010 my husband and I had quite a scare with our Bernese Mountain Dog, Pennsy. She had 3 grand mal seizures within 12 hours, and lost her gag and swallowing reflexes. My husband found her in the floor almost comatose when he returned from work with no muscle control, tongue hanging out of mouth, shallow labored breathing, urine around the floor where she left signs of pacing before she collapsed.

    We rushed her to the vet, where they gave her Vailum to stop the seizure and get her stable-enough to transport to the North Carolina State University Vet Teaching Hospital in town. We rushed her there, where she had another seizure when we arrived. They gave her oxygen, anti-seizure medication, and monitored her closely. She spent 48 hours in the hospital in ICU and Intermediate ICU. Both ER vets said she was in critical condition when they first saw her, and told us later that upon initial examination they doubted she would survive to come home with us.

    I had seen Donato’s story on the Berner-L, a Bernese Mountain Dog listserv, and found two varieties of mushrooms around our Lob lolly Pine trees in the backyard. I started researching more about mushrooms. I was also connected with Diana Gerba, who put me in touch with the National Mushroom experts, and I submitted a Poison Report at

    We learned through the report and photos I submitted that we had two types in our yard–red Russula (this one only causes mild symptoms and wasn’t the culprit), and Amanita pantherina (complex) in varying stages of growth and decay. This was the mushroom that caused the problems.

    Michael Berg of the NAMYCO said, \Dogs love to eat this mushroom and your experience is typical of what happens. There will be no long term consequences – but some dogs eat this mushroom again and again and again – on rare occasions death can result.\ Pennsy has never been one to randomly eat stuff from the yard or house, so we were surprised she ate these, but apparently they have a smell that dogs like.

    Thankfully Pennsy has fully recovered from this scary episode, and we hope to take her off the Seizure medicine at her 6 month check up later this month. We are just starting to see mushrooms growing in our yard, so we now begin a vigilant watch to discover and dig up these mushrooms. I don’t ever want to go through another mushroom episode like we did in October.

    Suzanne Miller & Pennsy (5 yr old female Bernese Mountain Dog)
    Raleigh, NC

  5. I live just west of Philomath, Oregon, in the foothills of the Coast Range, and we have a species of mushroom here that is quite poisonous, the species name is Scleroderma. It also likes dry ground, and grows near the surface of the ground, where it can sometimes be seen as a golden, globular shape just breaking the surface of dry soil or forest duff. It develops a dry, hard skin on the fruiting body, the origin of the species name. When opened, it can be mistaken for the false truffle mushroom, and is seemingly tasty, as more than one of my dogs through the years has dug them up, and consumed them, leading to liver damage requiring hospitalization and IV fluids. My dogs all survived, thankfully, and no more mushroom ingestion will occur now, as we have covered our front yard in paving blocks, and no ‘shrooms will sprout there again!

  6. Fortunately, very few mushrooms can be seen where we go and our guys are completely uninterested in any mushrooms at all.

  7. I know Diana, too, and also knew Donato. Diana’s research has been very thorough; she has consulted mycologists, forestry specialists, and biologists in trying to understand how the A. phalloides appeared where it did and why it’s appearing in heretofore never seen places.

    ==> It is changing genetically. Although for generations the mushroom has been found under and near oak trees, it can now be found under pine trees. Although it was previously accustomed to moist environments, it can now be found in DRY ones. Although it previously decayed without an odor, it now decays with the odor of DEAD FISH, one of the strongest temptations there is to a dog.

    Although the advice has always been to not pick or let children/pets near any strange growths out of the ground, this warning is now intensified by orders of magnitude due to the incredible expansion and metamorphosis of Amanita phalloides, the Death Cap mushroom (also known as the Destroyer).

    Remember: these mushrooms can now be found under or near pine trees in dry circumstances, and they may smell like fish. OR they may be found under or near oak trees in wet/moist circumstances with little or no odor. OR they may be found in some combination of these circumstances.

    AND they have now been found in the Sierras up to at least 6,000 feet elevation, where previously they were a sea-level plant. This was reported to me first-hand by another owner of Bernese Mountain Dogs, who found them on her own property.

    Donato was an amazing dog. Please don’t let him have died in vain: maintain vigilance *everywhere* and clear your yard and walking areas of any mushrooms at all. Better safe than sorry, and who knows what the next mutation of A. phalloides will LOOK like?

  8. Most mushroom species are not toxic, but those that are tend to be lethal. You might gain some peace of mind by having the mushrooms in your yard identified.

  9. Wow, we get mushrooms growing in our lawn at certain times of the year and we’ve always known they’re not safe to eat, for humans or animals, but never knew exactly why or just how deadly they really are!!! Thank you so much for the information and I am now even MORE comfortable with my decision to keep my dog crated (in a LARGE crate) when I am not home in order to keep her safe from even the possibility of escaping the yard or getting into something that could harm her. I’ve waffled back and forth over the past two and a half years about whether to keep crating her when no one is home or to just let her have free reign of the house and yard. While I could argue great points for either side of this choice, I know for me and my girl that she is safest in her huge comfy crate with her blankets and water bottle when I am not home.