Mushroom Poisoning in Dogs: What Owners Need to Know

January 5, 2022 - 6 min read
A dog staring at a wild mushroom

Wild mushrooms are common in autumn and can be found in woodlands, parks and even your own gardens. But if you have the sort of dog that tends to hoover up objects on a walk, you need to be aware of poisonous species of fungus.

Some wild mushrooms can even be lethally toxic to pets. And since they tend to spring up overnight in wet, mild weather, they can be hard to avoid.

Here’s what you need to know to keep your dog safe, and what to do if your dog does eat wild mushrooms.

Signs and Symptoms of Mushroom Poisoning in Dogs

Your pet can show a variety of symptoms depending on the type of mushroom they’ve eaten, including:

  • Vomiting

  • Diarrhea

  • Tummy ache

  • Excessive salivation and drooling

  • Lethargy

  • Wobbling, loss of balance

  • Yellowing of the white of the eyes or skin and gums

  • Seizures

  • Loss of motor control

  • Collapse

Veterinary surgeon Dr. Sophie Bell says: “It's important to note that for some mushrooms the reaction can be nearly instant (within two hours) and for others, the effects can be delayed. Your dog could appear normal for around 12 hours post-ingestion before symptoms begin.

“The 'wait and see' approach is never advised. If you suspect your dog may have consumed a toxic mushroom, it's best to take immediate action.”

What to Do if Your Dog Has Ingested a Toxic Mushroom

Dr. Bell’s message is clear: “Get them to the vet as soon as possible,” she says.

“Take a picture, or better still a sample of the mushroom eaten, if possible, for identification and for a better understanding of the treatment needed. Owners shouldn't try to Google and identify the mushroom themselves, as they can easily get it wrong."

But what if your dog ate a mushroom and you didn’t see it happen?

“You may be unaware your dog’s eaten a mushroom,” says Dr. Bell. “If you see neurological signs, agitation, vocalization/odd behaviors following a walk, get them to the vet's."

“Then, if you can, re-walk the walk you took with your dog to look for clues of what they may have eaten.”

The symptoms can be quite frightening, so stay calm and act fast. “If your pet starts to have seizures due to mushroom toxicity, try to keep them cool on your way to the vet's by spraying cool water on the paw pads, using air-conditioning in the car, and trying to remain as quiet as possible, which includes not talking to them.”

ManyPets pet insurance covers emergency veterinary care, video vet calls, and poison control consults, so you can be covered in an emergency.

Common Poisonous Mushrooms in North America

Here are some of the potentially deadly fungi your dog could find on walks and in your garden.

Fool’s Funnel

This is poisonous Mushroom is found in Europe and North America. Fools Funnel mushrooms often appear in parks, gardens and by the road. They can be hard to spot, as they only grow to about 2 inches. They are often seen in small groups or rings.

The first signs of being poisoned by Fool's Funnel are excessive salivating and sweating, which can be observed within half an hour of ingestion. Abdominal pains, sickness and diarrhea usually follow.

Death Cap

This is the deadliest fungus known — responsible for the vast majority of mushroom-related fatalities in humans — and it’s common in western North America. Ingestion of just half a cap can be lethal.

Symptoms usually appear within 6 to 24 hours. It starts with vomiting, diarrhea and severe abdominal pain, eventually leading to kidney and liver failure.

Funeral Bell

This is a small mushroom that grows in clusters from tree bark or stumps, and it can be found on multiple continents, including North America. It grows in mixed or evergreen woodlands. Its toxins are similar to those of the death cap. Initial symptoms include severe abdominal pain, vomiting, and diarrhea.

It can lead to kidney and liver damage, hypothermia, and death if not treated promptly.

Angel's Wings

Despite its beauty, this mushroom is thought to be neurotoxic. It can be found on multiple continents, including North America. Several cases of severe neurological damage in humans have been reported after ingesting it. So it is perhaps best admired from afar.

It can be found in evergreen woodland. It grows on decaying wood branches, bark and stumps.

Fly Agaric

Found on multiple contents including North America, Fly Agaric can sprout quickly and can kill dogs if they eat enough. It grows in woodland and heathland among birch, pine or spruce.

Symptoms appear after around 30 to 90 minutes and peak within three hours. They include nausea, drowsiness, twitching, and seizures.

The effects are likely to vary depending on the size, age and metabolism of your dog, with similar doses potentially causing quite different reactions.

This list isn't 100% comprehensive, but it's a start. Our vet expert Dr. Sophie Bell has one simple message for pet parents: “Always seek advice if you're worried your dog might have ingested something poisonous. Looks can be deceiving and mushrooms can vary from these images. So it’s better to be safe than sorry if you think they’ve eaten anything similar.”

How Do You Know if a Mushroom Is Safe or Not?

It’s nearly impossible to know for sure. Many harmless mushrooms have "evil" twins that are poisonous. It might be tricky, even for an expert, to tell the difference just by looking at it.

So the bottom line is, it’s best to discourage your dog from nibbling or sniffing wild mushrooms. If you spot any in your garden, remove them.

Getting rid of mushrooms can be difficult, especially in autumn when it’s often rainy and mild. And you also have to be careful about how you do it. Mowing or raking might distribute more spores around your garden.

If you spot one particular area of your garden or yard where they usually appear, you could try to dig out the soil and remove any potential food source, such as decomposing wood chips or other organic matter.

Using a nitrogen-based fertilizer is another tactic you could try. The nitrogen will speed up the decomposition of any organic matter that the mushrooms use for nutrients. But do make sure that the fertilizer’s safe for pets and wildlife.

Pluck out any mushrooms you spot as soon as possible to prevent their spores from spreading and producing more mushrooms. Dispose of them carefully to prevent spores from finding their way to other places where fungi might thrive.

Other Poisonous Plants for Dogs

Mushrooms aren’t the only plant-based peril for your dog. Here are a few more of nature’s toxins you might encounter during a dog walk:

Daffodils: The entire daffodil plant is toxic to dogs, but toxins are especially concentrated in the bulb. Dogs only need to ingest a relatively small amount to become ill. The problem is how common the plant is — your dog can encounter daffodils in your own garden or yard, or out and about on walks. You might think it's unlikely that your pup will eat the flower, but be vigilant and make sure they don't dig up and chew the bulbs.

Signs of toxicity include drooling, pain, and tiredness, but these can develop into more serious symptoms if your pet’s ingested a large amount.

Clematis: Like daffodils, this is an extremely common plant for your dog to find, and one most owners don’t know is poisonous. While most dogs aren’t particularly prone to chewing up flowers, particularly bitter ones like this, curious puppies might do so — and unfortunately these plants are more dangerous to them than to larger dogs.

Drooling is a symptom, as well as vomiting and diarrhea.

Blue-Green Algae: If your dog’s a swimmer, check the water for a green or blueish scum, especially in non-flowing water like ponds or lakes. Blue-green algae isn’ technically a plant, but it looks like one and it can be found in both salt water and fresh water. It’s actually a "cyanobacteria" that can be highly toxic to dogs, causing heart, liver and neurological problems. Your dog can become unwell just by bathing in the water, even if they don’t drink it.

Along with the symptoms of poisoning listed above, it can also cause paralysis or seizures; seek immediate treatment if you suspect your dog’s encountered blue-green algae.

There are plenty more examples with varying levels of toxicity. The ASPCA has compiled an extremely comprehensive list of which plants are toxic to dogs.

If you think your dog’s eaten a wild mushroom or any of the other plants mentioned, follow Dr. Bell’s advice and speak to a vet immediately.

Irina Wells
Content Marketing Executive

Irina is a former content marketing executive for ManyPets. She has contributed to a number of personal finance sites, including Loot Financial Services and Claro Money.