Since ethylene glycol is an alcohol, the early signs of poisoning resemble drunkenness; euphoria and/or delirium, wobbly gait, uncoordinated movements, nausea as evidenced by excessive salivation, lip smacking, dry heaving, and vomiting. This phase can persist for about six hours and the animal may appear to be better, not so! If untreated, the signs progress to excessive urination, diarrhea, rapid heart rate, depression, weakness and eventually into fainting, tremors, convulsive seizures, and coma, all signs of kidney failure.
If you arrive at the animal hospital in time and give a history of your pet ingesting antifreeze, or your veterinarian runs appropriate tests and makes the diagnosis, before signs of kidney failure occur, there is a good chance your pet will be saved. Treatment involves the induction of vomiting. Using activated charcoal to bind any ethylene glycol still in the digestive tract is not effective, but may be indicated when other toxins are suspected. Since 1996, your veterinarian has had access to fomepizole (Antizol-Vet). This drug is an effective antidote, if administered intravenously before kidney damage occurs. Back in the olden days, we used grain alcohol as an antidote, significantly less expensive than fomepizole. Alcohol dehydrogenase has about 100 times the affinity for grain alcohol than it does for ethylene glycol. When used as an antidote, the liver metabolizes less ethylene glycol and fewer oxalate crystals form. Depending upon the severity of kidney damage it still might be possible to save your pet with aggressive fluid therapy to flush the kidneys, and other supportive treatment. Some specialty practices may be equipped to provide kidney (renal) dialysis. You do not want to know how much a kidney transplant will cost, but it is possible, in both dogs and cats, in specialized centers with the necessary equipment and experience.
Seattle author David R. Gross practiced veterinary medicine for ten years. He returned to school and earned his PhD in cardiovascular physiology, then he taught and did research in that field for more than three decades. Check out his latest book, Travels with Charlize.
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