Antifreeze Toxicities in Pets

May 1, 2015

Antifreeze poisoning is one of the most common forms of poisoning in small animals, and this is because it is so commonly found in households. Antifreeze poisoning typically happens when antifreeze drips from a car’s radiator, where it is licked off the ground and ingested by a pet. Your cat or dog could also come into contact with antifreeze that has been added to a toilet bowl. This happens in homes where the residents will use antifreeze to "winterize" their pipes. Even if you do not do this in your own home, it is something to be aware of when visiting other homes, or when vacationing at a winter residence.


Ethylene glycol is the lethal chemical in antifreeze. It is a sweet tasting substance, which is why so many pets like it. And it doesn't take a large amount to cause fatal damage to the system. Less than 3 ounces (or 88 ml) is enough to poison a medium-sized dog. Antifreeze toxicity affects the brain, liver, and kidneys.


Common signs of antifreeze poisoning in dogs and cats include:


  • Drunken behavior including wobbly, uncoordinated movements

  • Euphoria/Delirium

  • Nausea/Vomiting

  • Excessive urination

  • Diarrhea

  • Rapid heart beat

  • Depression

  • Weakness

  • Seizures/Convulsions/Shaking tremors

  • Fainting

  • Coma


If you suspect antifreeze poisoning in your pet you need to get him or her to your veterinarian immediately. The veterinarian will need to perform a thorough physical exam and will need to get a complete medical history including the reasons for suspecting antifreeze ingestion. Most likely the veterinarian will perform a complete blood chemistry profile and a urinalysis. Immediate veterinary care increases the chances of survival where antifreeze poisoning is concerned.


 It is possible for dogs and cats to survive antifreeze ingestion with aggressive therapy, but they usually develop irreversible kidney failure and most are not so lucky to survive. The best thing is to prevent antifreeze poisoning from ever occurring.


 Antifreeze poisoning can be easily avoided by following a few simple precautions:


1. Keep antifreeze containers tightly closed and stored out of the reach of pets.

2. Take care not to spill antifreeze, and if it is spilled, ensure that it is immediately and thoroughly cleaned up.

3. Dispose of used antifreeze containers properly.

4. Check the radiator of your car regularly, and repair leaks immediately.

5. Do not allow your dog to wander unattended where there is access to antifreeze (e.g., roads, gutters, garages, and driveways).


 The U.S. Food and Drug Administration has labeled propylene glycol safe and it is now used for antifreeze. Be sure to use antifreeze with this ingredient instead, to keep your pet safer from accidental poisoning.