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Fall Toxins Poisonous to Dogs & Cats

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The start of fall brings new seasonal household items that pose a threat to the safety of our pets. These common household items can cause serious problems if ingested by animals. Here is the list of seasonal products that the veterinarians at Pet Poison Helpline recommend keeping away from pets.


While most mushrooms are generally non-toxic, certain types can be very dangerous. One of the most dangerous is the Amanita phalloides or death cap mushroom which is found throughout the United States. The proper identification of mushrooms is extremely difficult and often only done by experts. Therefore, it is wise to consider all ingestions of unidentified mushrooms as toxic until proven otherwise. Depending on what type of mushroom is ingested, symptoms include vomiting, diarrhea, abdominal pain, depression, tremors, and seizures, with liver and kidney damage occurring later. Pet owners should scour their yard frequently to get rid of any mushrooms.



While you may think these white balls are benign, they are not. Mothballs typically contain either paradichlorobenzene or naphthalene. While the old fashioned mothballs (naphthalene) are often considered more toxic, both can be deadly. Symptoms include vomiting, severe abdominal pain, tremors, weakness, possible kidney or liver failure, and severe abnormality of your pet’s red blood cells.


As people prepare their boats, cars or cabins for winter, pets may inadvertently be exposed to antifreeze. As little as one teaspoon in a cat or a tablespoon or two for dogs, depending on the size of animal, can be fatal. Signs of early poisoning include acting drunk or uncoordinated, excessive thirst, and lethargy. While signs may seem to improve after eight to twelve hours, internal damage is actually worsening, and crystals develop in the kidneys, which result in acute kidney failure. Immediate treatment with an antidote is vital.

Mouse and Rat Poisons (Rodenticides):

Rodenticide Bait BlocksAs you prepare to winterize your garage, cabin, or house, make sure to place poisonous baits in areas where your pet cannot reach them (e.g., high up on shelves, hidden behind work spaces, etc.). “Rodenticides also pose the potential for relay toxicity,” said Dr. Ahna Brutlag, assistant director of veterinary services at Pet Poison Helpline. “In other words, if your dog eats a large number of dead mice poisoned by rodenticides, they can experience secondary effects.” Because there are several different types of chemicals in mouse and rat poisons, all with different active ingredients and types of action, it is imperative to keep your pets away from all of these potentially dangerous poisons.

Compost bins or piles:

Piles of decomposing and decaying organic matter and molding food products in your backyard compost pile have the potential to contain ‘tremorgenic mycotoxins’, meaning molds which cause tremors. Even small amounts ingested can result in tremors or seizures within 30 minutes to several hours.

Red maple leaves:

Horse lovers, beware. As little as one pound of dried maple leaves blowing into your horse’s pasture can be toxic. When ingested, these leaves result in a severe hemolytic anemia – it causes red blood cells to rupture, causing weakness, pale gums, an elevated heart rate and shock.


The best thing any pet owner can do is to be educated on common household toxins, and to make sure you pet-proof your house appropriately. Make sure to keep all these products in labeled, tightly-sealed containers out of your pet’s reach. When in doubt, if you think your pet has been poisoned, contact your veterinarian or Pet Poison Helpline at 800-213-6680 with any questions or concerns.