Mar 20

Pet Poisons and Common Toxicities

Pet Poisons and Common Toxicities

Accidental ingestions are one of the most common pet emergencies.  All too often we hear, “My pet would not eat that,” “’I didn’t think he would get on the counter,” “I didn’t think she could reach that plant,” etc.  If you find yourself faced with one of these scenarios, knowing a few basic things may help your pet recover uneventfully (or help you to prevent the toxic ingestion in the first place).

Common Toxicities in Dogs & Cats at Friendship:

  • NSAIDs – (non-steroidal anti-inflammatory drugs), including human products (such as Advil, Aleve, etc.) as well as veterinary products (Rimadyl, Metacam, etc.)
  • Xylitol – sugar free gum additive
  • Chocolate
  • Grapes and Raisins (dogs)
  • Rat Poison
  • Lilies (cats)
  • Marijuana
  • Antifreeze (ethylene glycol)

In addition to the NSAIDs listed above, it’s important to NEVER EVER give your pet a human medication without speaking with a veterinarian beforehand.  Not only are our pets potentially 1/10th of our size or less, their ability to metabolize some medications may differ greatly from our own.

If your pet does ingest a potentially toxic substance, you must first answer a few questions:

WHAT:  What was ingested?  Is it toxic?

Unsure?  Call ASPCA Animal Poison Control Center at 1-888-426-4435, Pet Poison Hotline at 1-800-213-6680, or your local veterinarian.  Please always bring the packaging with you to the vet’s office if you are unsure.  Contacting an animal poison control agency may be very helpful in determining whether the substance(s) ingested are toxic and what the recommended treatment would be – particularly if multiple human medications are ingested or an unknown amount of a substance is ingested.

HOW MUCH and WHEN:  Time of ingestion and amount are essential pieces of information and may dictate treatments provided.  Certain toxicities are dose-dependent (like NSAIDs and chocolate), others are not (grapes/raisins) and some can cause unexpected signs in pets.


Examples of common human and veterinary NSAIDs include aspirin, ibuprofen (Advil®), naproxen (Aleve®), celecoxib (Celebrex®), piroxicam, meloxicam (Metacam®), carprofen (Rimadyl®, Novox®), and robenacoxib (Onsior®). This is not an exhaustive list.

Depending on the dose ingested, clinical signs of toxicity can include gastrointestinal upset (vomiting/diarrhea, decreased appetite), stomach and intestinal ulcers and erosion, kidney failure, bleeding disorders or even liver failure or seizures and coma.  Prognosis can be excellent with prompt treatment with decontamination, medications to protect the gastro-intestinal tract, and IV fluids to prevent kidney damage.  Delays in treatment may result in permanent or even fatal damage to the kidneys.

Also, although acetaminophen (Tylenol®) is not a true NSAID, it can be deadly, particularly for cats.  It can cause red blood cell damage, liver failure and cardiovascular damage.

Xylitol is an additive in sugar free gum:  it can cause hypoglycemia (low blood sugar) and sometimes liver damage.  Sensitivity to liver damage can vary from dog to dog and the magnitude of damage to the liver may not be directly related to the dose.  Prompt treatment may prevent toxic effects.

Chocolate contains methylxanthines (theobromine and caffeine).  This toxicity is dose-dependent.  Lower doses can cause gastrointestinal signs (vomiting, diarrhea), higher doses can cause high heart rate, abnormal heart rhythms, agitation and even seizures.  Pancreatitis can be a delayed effect from chocolate ingestion, particularly if the chocolate contained a lot of fat (e.g. truffles).  Prompt treatment may prevent toxic effects.

Grapes and Raisins:
These can cause kidney failure in dogs.  The mechanism is unknown and the type and amount of fruit ingested does not predict the signs.  Once kidney failure is present, it may be irreversible in some cases.  Again, prompt treatment with decontamination and IV fluids may prevent toxicity.

Rat Poison:
There are 3 main types of rat poison available in the U.S.  Each has a different mechanism of action and therefore its own treatment and monitoring plan.

1) Anticoagulant:  interferes with the body’s ability to clot blood and therefore causes internal bleeding.  Signs are often not present for 48-72 hours.  May require treatment with Vitamin K supplementation for a month in some cases.  If treatment is not started until after we see signs of bleeding, some pets may require plasma transfusions.  Prompt treatment with decontamination may be the only treatment required if patients come to the hospital quickly.

2) Bromathalin: neurotoxic.  Can cause acute and delayed neurological sign such as seizures, brain swelling, hyperexciteability, wobbly gait, weakness, depression or paralysis.  Treatment is largely supportive in nature.

3) Cholecalciferol:  vitamin D3 toxicosis causing acute kidney failure and arrhythmias.  Treatments may include IV fluids and medications to help correct abnormalities in calcium metabolism.

All the parts of the plant are toxic (pollen, leaves, stems and petals) and can cause kidney failure in cats..  Easter lilies are the most common exposure.  Peace lilies are not toxic to the kidneys.  The ASPCA’s Animal Poison Control Center has a guide to toxic and nontoxic plants that contains helpful photos.  Prompt and aggressive treatment may prevent kidney failure.  Once kidney failure sets in, it may be irreversible.

While marijuana does not cause organ damage, it can cause severe depression, weakness, low heart rate, low body temperature, low blood pressure, urinary incontinence, seizures or even coma.  Treatment is largely supportive in nature.

Ethylene Glycol:
EG is found in antifreeze.  It can initially cause neurologic signs (wobbly gait, depression), and non-specific gastro-intestinal signs such as vomiting.  It can also cause kidney failure, which may be irreversible.  Prompt treatment is necessary for a good outcome.


If the toxic ingestion is recent, decontamination through emesis (vomiting) is often the first treatment.  There are some toxins for which emesis is not indicated, and there are risks associated with inducing vomiting, so always consult a veterinary professional in any potentially toxic ingestion.

Additional treatments may include activated charcoal to help bind additional toxins in the intestinal tract, intravenous fluid therapy, and medications to protect the liver or gastro-intestinal tract.  Some toxicities are treated with specific medications or antidotes, blood or plasma transfusions and even hemodialysis.  Many toxicities also require serial monitoring of kidney or liver values, blood clotting tests, or blood pressure and heart rate (ECG) monitoring. Most toxicities begin to cause symptoms or changes in blood work within 12-72 hours after ingestion.  If left untreated for a prolonged period, some toxicities can cause irreversible or even fatal organ damage.  Fortunately, most pets will do very well following toxic ingestions if treated promptly.

It’s important to remember, there are far more toxic substances than discussed here.  If you are worried that your pet has ingested a potential toxin, please contact your veterinarian or an Animal Poison Control hotline.  Time may be of the essence, so please reach out for help quickly!


Dr. Genevieve Schildroth is a staff doctor on our Emergency & Critical Care service.  She graduated from the University of Wisconsin School of Veterinary Medicine before relocating to New York, where she practiced for several years before joining the Friendship team.  She currently lives in DC with her dogs Cooper and Lottie Brown.



* Featured image courtesy of Vegas Animal 411.


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