Hidden Valley Animal Clinic

100 Oakhurst Drive
McMurray, PA 15317



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.