Antifreeze Poisoning in Dogs and Cats

Antifreeze poisoning is the most common poisoning of dogs and cats in the United States. Over 10,000 dogs and cats are poisoned with automotive antifreeze each year.


Antifreeze is an engine coolant. The ingredient found in antifreeze that is poisonous to dogs and cats, is ethylene glycol, which make up 95 percent of the antifreeze. Ethylene glycol is a transparent greenish color that is sweet tasting to dogs and cats. A small taste will poison your pet. Cats are four times more sensitive to antifreeze then dogs. Only 1 to 2 teaspoons will poison a cat, and only 3 tablespoons will poison a medium size dog. Antifreeze poisoning will cause an immediate and long term effect on your pet.


Once ingested your pet may experience the following,

  • Intoxication behavior
  • Vomiting
  • Increased thirst
  • Diarrhea
  • Seizure's
  • Increased heart beat
  • Rapid breathing
  • Weakness
  • Coma

Within 30 minutes after ingestion, your pet will act as if he is intoxicated. This will continue for up to 6 hours. Vomiting and diarrhea will occur because the ethylene glycol is irritating to the stomach. They will drink excessively which will cause them to urinate more frequently. The wobbly drunk affect will diminish and your dog or cat may seem to be recovering. A few days later, your pet will become worse, symptoms like depression, weakness and dehydration can occur. This is due to the Ethylene Glycol being metabolized by the liver and kidneys. Once the kidneys tubular cells are destroyed, damaging the kidneys, the poison will then affect the Central Nervous System. There is no treatment that will reverse this stage.


If you think that your dog or cat has been poisoned by antifreeze, you need to call your veterinarian immediately. Your veterinarian may tell you to induce vomiting. To induce vomiting, you need to administer hydrogen peroxide to your dog or cat. Give 1 teaspoon-full per five pounds of body weight. Do not give more than 3 teaspoons full at a time. This can be done three times, given 10 minutes apart. If the three doses of hydrogen peroxide does not induce vomiting, do not give more.

Do not induce vomiting if your pet is having trouble breathing, is in shock, or is unconscious. Even if vomiting has occurred your pet still needs to be rushed to a Veterinarian. Blood work will be preformed to see if the liver and kidney enzymes are elevated. It is important that you bring all evidence that you have that relates to the poisoning so that they can properly diagnose and treat your pet. They will monitor your pet and give necessary treatment. Antidote are given to prevent the further absorption of the poison.


There are actions that can be done to prevent your dog or cat from getting antifreeze poisoning.

  • Switch to propylene-glycol based antifreeze. This is less toxic than ethylene glycol.
  • Check for antifreeze leaks in your car.
  • Clean up any antifreeze spills.
  • Keep antifreeze in a tight container and in high places.
  • Dispose of antifreeze properly.

If detected early, dogs and cat can survive from antifreeze poisoning. Your dog or cat may experience long term kidney failure as a result from the poisoning.