Antifreeze poisoning is a hazard not just from radiator fluid in your car, but can be found in brake fluids, deicers, condensers, heat exchange units, home solar units, some imported snow globes, portable basketball post-bases, and in winterized toilets in recreation vehicles and cabins. Although there are three commonly used antifreeze solutions, ethylene glycol is the most toxic. The other two antifreeze solutions, methanol and propylene glycol, are much safer and accidental ingestion’s are more easily managed.
Species sensitivity to the toxic effects of ethylene glycol varies with cats, rabbits, and humans being the most sensitive. Dogs, cattle, pigs, and rodents have an intermediate sensitivity. The most common source of ethylene glycol toxicity is from commercial antifreeze products, which contain approximately 95% ethylene glycol. The toxic dose of ethylene glycol is as low as one teaspoon when ingested by a cat or a tablespoon or two for a dog (depending on their size), and can be fatal.
Clinical signs of early poisoning include acting drunk, excessive thirst, and lethargy. While signs may seem to improve after eight to twelve hours, internal damage is actually worsening, and crystals develop in the kidneys resulting in acute kidney failure. Immediate treatment with an antidote (fomepizole or ethanol) is vital. As the antidote only works if given within the first 3 hours for cats and 8-12 hours for dogs, it’s imperative that you seek veterinary care immediately for blood testing for antifreeze poisoning (including an ethylene glycol test and venous blood gas test).