LAMORINDA WEEKLY | Warning for pets and people: Don't eat the wild mushrooms!


Dr. Mona Miller lives in Lafayette with her son, two cats and yellow Labrador. She attended UC Berkeley as an undergraduate, and received her DVM from UC Davis. She has been happy to call Lafayette home since 2001. She can be reached via email at MonaSDVM@aol.com. She welcomes questions from readers that may get incorporated into a column.

Wet winter weather brings conditions perfect for soil fungi to grow. The vast majority of the thousands of types of mushrooms in the United States are non-toxic, but there are about 100 species that are toxic, and even fatal. Unless you have thorough knowledge and experience in identifying wild mushrooms, it is best to remove these from the yard, or even eliminate access by your furry dog friend. Toxic mushrooms often tend to have look-alike non-toxic counterparts, so it can be very difficult to tell the difference between these. As a side note, dogs do not necessarily make the association between what they have eaten and feeling sick, so a dog can be a repeat mushroom eater. Cats can also be prone to mushroom toxicity, but at a much lower level, since they tend to be more discriminating than dogs when eating items in the yard.

Toxic mushrooms can cause a variety of symptoms, ranging from mild intestinal upset to severe liver damage to fatal neurologic disease. It can take a matter of a few hours to a few days for some symptoms to develop. The milder toxicities are generally stomach upset, with nausea, vomiting and diarrhea showing within a few hours and lasting a couple of days. These cases usually resolve with some supportive care such as fluid supplementation, antacids and anti-nausea medication.

A number of mushroom species can cause initial intestinal upset within hours, and then progress to severe liver failure a few days later. The most common species is Amanita ("death cap" mushroom is Amanita phalloides), which is a look-alike mushroom to other non-toxic species. The classic Amanita is the red cap covered in creamy white dots. However, there are Amanita species that are dull gray and appear to be "safe."

Other types of mushrooms contain muscarine and causes the SLUDGE set of symptoms: salivation, lacrimation (tearing from the eyes), urination, diarrhea. This set of symptoms is also seen in some pesticides and former flea control products.

The hallucinogenic mushrooms, such as the Psilocybe species, are generally not life-threatening when eaten by a dog. However, these can cause all kinds of neurologic signs, as one would expect from a hallucinogen - howling, wobbliness, rapid eye movements (nystagmus), high body temperature, and abnormal behavior.

Since mushroom identification can be very difficult, veterinary treatment is based on a "worst case scenario" until proven otherwise. Thus, a known mushroom ingestion is cause for urgent/emergency care. If your dog has eaten a mushroom within the past couple of hours, the veterinarian might give an injection to make the dog vomit anything still left in the stomach. This patient should have blood tests to monitor liver values over the next few days, fluid and medication support, and monitoring for tremors or seizures.

Here are some website resources to learn more:

Veterinarypartner.vin.com - Mushroom Poisoning in Dogs and Cats

https://veterinarypartner.vin.com/default.aspx?pid=19239&id=10020259

ASPCA https://www.aspcapro.org/resource/mushroom-poisoning-dogs