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POISONOUS/TOXIC SUBSTANCES

If your pet should happen to be poisoned by a hazardous substance, contact your veterinarian immediately.  Do not try to induce vomiting without consulting a veterinarian first. 

The ASPCA Animal Poison Control Center (APCC) is a good resource for any animal poison-related emergency, 24 hours a day, 365 days a year.  If you think that your pet may have ingested a potentially poisonous substance, make the call that can make all the difference: 1-888-426-4435  (A $60 consultation fee may be applied to your credit card).

Always be sure to keep the phone number of your vet and the Animal Poison Control Center near your phone.


Antifreeze (Ethylene Glycol)

Antifreeze poisoning is fatal in any animal that is not treated within 6-8 hours of ingestion.  If you suspect, for any reason, that your pet has ingested antifreeze, seek immediate medical treatment. 

Antifreeze poisoning normally occurs when pet is exposed to antifreeze leaking from a car's cooling system or when antifreeze is changed and left out in the garage.  Sometimes antifreeze is placed in home plumbing systems when heat will not be maintained during winter months (such as a summer cottage).  Pets have been exposed to antifreeze poisoning maliciously in some instances, as well.

Antifreeze is extremely toxic to pets, even in small doses.  As little as one teaspoonful of antifreeze (5ml) can kill a 10-pound animal.  Unfortunately, antifreeze tastes good to dogs and cats and therefore ingestion of large quantities is common.

Initial symptoms of toxicity develop in 1-12 hours, depending on the dose ingested.  These symptoms include:

  • vomiting,
  • diarrhea,
  • depression,
  • seizure.

These signs normally last about 12 hours, causing some owners to think the danger has passed.  (Cats are less likely to recover from the initial signs.)  At this time, the antifreeze has irreversibly damaged the kidneys.  The kidney problems usually show up one to three days after ingestion of the antifreeze.  Urine output may initially increase but then decreases until urine is not produced at all.  This severe renal failure causes:

  • vomiting
  • lack of appetite,
  • sores in the mouth,
  • bad breath,
  • severe depression,
  • coma and death.

Chocolate

Most people are aware that chocolate is poisonous for pets but don't know how much it takes to cause a toxic reaction.  Chocolate contains theobromine and dogs (and other domestic animals) metabolize theobromine more slowly than humans which allows for greater toxicity when consumed in smaller quantities. Dogs are more likely to eat chocolate than cats, many cats won't eat it. However, if your cat does eat chocolate, treat the situation as life threatening, since cats are small and it takes less chocolate to be dangerous.

Different types of chocolate contain vastly different concentrations of theobromine:  milk chocolate is the least toxic, semi-sweet chocolate is more toxic, and Baker's (unsweetened) chocolate is the most toxic.  The more expensive dark chocolate candy is worse than semi-sweet and can approach Baker's chocolate in its theobromine concentration.

For a chocolate ingestion to be life-threatening your dog would need to eat:

  • milk chocolate – 1 ounce for every pound the dog weighs
  • semi-sweet chocolate – 1 ounce for every 3 pounds the dog weighs
  • baker's chocolate – 1 ounce for every 10 pounds the dog weighs
Potentially Fatal Chocolate Ingestion
for Dogs
Dog's WeightMilk ChocolateSemi-sweet ChocolateBaker's Chocolate
10 lbs10 oz. 3 oz. 1 oz.
(one square)
50 lbs50 oz. 16 oz. 5 oz.
(five squares)

Symptoms of of chocolate ingestion are:

  • Hyper excitability
  • Hyper irritability
  • Increased heart rate
  • Restlessness
  • Increased urination
  • Muscle tremors
  • Vomiting
  • Diarrhea

If you suspect your dog has eaten a large quantitity of chocolate within the last few hours, you should try to induce vomiting (see how to induce vomiting) and then seek immediate medical attention.

Chocolate ingestion in smaller quantities will often cause vomiting and diarrhea 12-24 hours after ingestion and may require medical treatment at that time.


Xylitol

Xylitol is an artifical sweetener found in many human "sugar free" products, such as gum, candies and other sweets.  This substance is safe for humans but is toxic to dogs and cats.

Xylitol causes a rapid release of the hormone insulin, causing a sudden decrease in blood glucose.  This in turn may cause the following symptoms:

  • Vomiting
  • Weakness
  • Ataxia (uncoordinated movements)
  • Depression
  • Seizures
  • Coma
  • Liver dysfunction and/or failure

Signs of toxicity can be seen as quickly as 30 minutes after ingestion. The degree of toxicity is related to the weight of the animal and how much xylitol the animal has ingested.

If you suspect that your pet has eaten a xylitol-containing sweet or food, please contact your veterinarian, Emergency Clinic, or the Animal Poison Control Center as soon as possible.  If it is soon after ingestion (before clinical signs develop), your vet may advise inducing vomiting.  (See: how to induce vomiting.)


Onions

Onions, in large quantities, can be toxic to dogs and cats.  The toxicity is dose dependent, so the bigger the animal, the more onion need be consumed to cause a toxicity.  The toxic effect of the onions are the same whether the product is raw, cooked or dehydrated. 

Onions damage red blood cells which can cause a severe type of hemolytic anemia.  The hemolytic episode usually occurs 3-7 days after onion ingestion.  Most cases of toxicity stem from one episode of large ingestion but daily feeding of onions could have a cumulative effect. 


Grapes and Raisins

Veterinarians are not sure exactly why grapes and raisins are toxic to both cats and dogs.  We do know that large quantities can damage the kidneys.  For this reason, it's unwise to feed these to your pet, even if small amounts are tolerated.  Also, avoid giving bits of baked goods or other foods that contain raisins.


Rodent/Pest Bait (Rat Poison)

Under Construction


Poisonous Plants

The list of potentially dangerous house plants and outdoor plants is extremely long. Identification of all the different types of poisonous plants is not possible here, but a selected list of the most common plants that can be toxic to your pet follows:

  • Alfalfa
  • Amaryllis
  • Angel's Trumpet
  • Arrowgrass - Can be fatal
  • Azalea
  • Bird of Paradise
  • Bittersweet, American - Berries can be fatal
  • Black Locust
  • Bleeding Heart
  • Buttercup
  • Calla, Lily, Wild, Yellow
  • Castor Bean - Can be fatal
  • Cherry Tree - Foliage and bark can cause cyanide poisoning
  • Cherry, Jerusalem, Ordinary, Christmas
  • Chinaberry
  • Chokecherry
  • Chrysanthemum, Pot, Spider
  • Coriara - Causes convulsions
  • Creeping Charlie
  • Crown of Thorns
  • Daffodil
  • Delphinium
  • Dieffenbachia - Can be fatal
  • Easter Lily - Can be fatal
  • Elderberry - Can cause cyanide poisoning
  • Elephant Ears
  • Fern, Bracken, Asparagus, Sprangeri
  • Foxglove
  • Hemlock, Poison, Water - Can be fatal
  • Hemp
  • Holly, English
  • Hyacinth
  • Hydrangea
  • Ivy, English, Ground, Poison, Glocal, Heart, Needlepoint, Ripple
  • Jack-in-the-Pulpit
  • Jasmine
  • Jimsonweed - Can be fatal
  • Larkspur
  • Lily-of-the-Valley - Can be fatal
  • Locoweed - Can be fatal
  • Lupine
  • Milkweed, Common
  • Mint, Purple
  • Mistletoe - Can be fatal
  • Moonweed - Causes convulsions
  • Mushrooms and Toadstools - Can be fatal
  • Nettles
  • Nightshade
  • Oleander - Can be fatal
  • Peach tree - Foliage and bark can cause cyanide poisoning
  • Philodendron - Can be fatal
  • Poinsettia
  • Pokeweed
  • Rhododendron
  • Rhubarb - Can cause convulsions and death
  • Skunk Cabbage
  • St. Johnswort
  • Thorn Apple
  • Tomato Vine
  • Tulip
  • Umbrella Plant - Can be fatal
  • Yew, Japanese, American, Ornamental, English

Symptoms will vary from animal to animal.  Some may eat these plants and will exhibit no symptoms; others will exhibit local irritants such as drooling, vomiting, diarrhea, irritation to the mouth and skin or swelling of the area around the mouth.  Extreme cases of poisoning may cause convulsions, tremors to the heart, respiratory and kidney problems, and in the most extreme cases, coma or even death.  It is good to note that most dogs and cats will vomit after chewing on plants.  This probably does not mean poisoning.  Only severe or persistent vomiting is a danger sign, especially when accompanied with one or more of the other symptoms.

Be sure to know the names of all the plants in and around your home and keep potentially toxic plants out of the areas accessible to your pet.