Deadly danger in the driveway
Vets dread winter. It’s not that we are more susceptible to the cold weather blues, but we know whenever winter hits hard, we are certain to see heart-breaking cases of ethylene glycol poisoning. These poor dogs and cats suffer terribly, and almost always die. Often clusters of poisoning occur in a neighbourhood: I decided to write this blog after a neighbour in Coxheath lost two of her lovely young kittens in rapid succession to this poison. Hopefully someone’s life will be saved if more people are made aware just how deadly this chemical is.
What is ethylene glycol?
Present in antifreeze, screen washes, de-icing sprays and brake fluid, this chemical lowers the freezing point of water. Diluted ethylene glycol is widely used to keep radiators, windscreen wash and garden ponds from freezing. Unfortunately, cats and dogs find the sweet taste of ethylene glycol irresistible, and drinking a tiny amount is usually fatal.
How deadly is the poison?
Cats only need to drink a teaspoon or less of antifreeze to lead to serious illness and even death. Fatal doses can be ingested by licking the antifreeze bottle or by foot-licking after walking through the puddle of de-icer left on the driveway. Dogs are slightly less susceptible, although one tablespoon of pure antifreeze can kill an average dog. When used to stop garden water features freezing, this deadly water will be too tempting for a dog or cat to ignore. Regrettably, malicious poisonings feature all too often in the press, when sick individuals deliberately poison cats (and other exposed wildlife).
How does ethylene glycol poison cats and dogs?
Ethylene glycol is broken down in the liver. This process produces other chemicals that severely damage the animal’s kidneys, often causing irreversible and fatal changes.
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. The animal may appear drunk, appear uncoordinated, and will often salivate or vomit. 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 body waste accumulation following kidney shut-down. Unfortunately, often initial signs are not seen, and the patient appears normal until kidney failure develops a few days after exposure.
What can I do if I suspect exposure?
THIS IS AN EMERGENCY.
If you have any suspicion that your pet has had contact with antifreeze (on the coat or feet or by lapping up water), call your vet without delay. Vomiting, wobbliness, confusion and traces of green dye on the fur of the muzzle, paws and tail are indicators of exposure.
Are there specific tests to prove that a patient has been exposed to ethylene glycol?
In the early stages, a simple urine test will detect the presence of calcium oxalate crystals which are one of the products formed after ingestion of the poison. As the poisoning takes hold, kidney damage develops, and blood tests will show how badly the kidneys are affected.
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. 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 treatment is left until signs of kidney failure appear the chances of recovery are significantly reduced and euthanasia is often the only humane option.
What steps can I take to protect my dog or cat?
If you have any products containing ethylene glycol such as antifreeze, make sure you store them safely away from children and animals. Use screen wash and de-icer sprays that do not contain ethylene glycol. If a car radiator has been drained and a splash of antifreeze remains on the floor, wipe it up completely and rinse the area thoroughly with water. Remember even a tiny amount on a cat’s feet (picked up if it walks through a spillage) may be fatal.
Simply being aware of your companion animal’s normal health and behaviour will help you to notice signs of illness. For example, if a normally healthy cat with outdoor access returns home and seems too quiet and is vomiting, seek advice from your veterinary practice immediately.