Cat & Dog - Antifreeze Poisoning

Ethylene glycol, the main constituent of antifreeze is poisonous for dogs and cats.  Statistically, in the UK each year more cats are poisoned than dogs, probably because more cats than dogs are able to access open containers of antifreeze stored on garage shelves.  More cases obviously occur during winter.

How does the poisoning occur?

Pets are attracted to the sweet taste of ethylene glycol.  Many will lap antifreeze spilled or leaking on to garage floors or driveways.  The main source of poisoning is the jug of antifreeze left on the garage shelf for instant top-up purposes on cold winter mornings.

What are the signs of antifreeze poisoning?

This depends on the amount of ethylene glycol ingested.  A small quantity of concentrated antifreeze can result in signs within an hour.  These involve depression, incoordination, and vomiting.  Sometimes there is excessive thirst and urination.  These signs can be followed by muscle twitching and in 12-24 hours acute renal (kidney) failure resulting in minimum urine production and depression, often with vomiting and excessive salivation.  Seizures and death can quickly follow due to increasing uraemia (failure of urine production).

What can I do?

If you have any suspicion that your pet has had contact with antifreeze, call us without delay.

Are there specific tests you can do?

Ethylene glycol is converted in the body to toxic products which cause irreversible damage to the kidneys.  Blood tests will show the extent of this kidney damage, and in addition a simple urine test will detect the presence of oxalate crystals which are one of the products formed after ingestion of the poison.

Is there an antidote?

Provided diagnosis is made before there is irreversible kidney damage, drugs are available to combat the ethylene glycol in the bloodstream.  Within hours of ingestion the ethylene glycol is converted into toxic products including calcium oxalate.  This is a major and not uncommon emergency.  If calcium oxalate crystals are detected in the urine, there is a history of possible antifreeze poisoning.  Intensive care (provided this is started before too much damage has occurred) involving intravenous fluids will often result in improvement in a very short time.

If it is left until the animal is showing signs of kidney failure, the chances of recovery are significantly reduced and euthanasia may need to be considered.