Ethylene Glycol Toxicity

Mainly present in antifreeze substances, ethylene glycol is very toxic to cats. Its sweet taste makes it appealing to them and it only takes a small amount to lead to death. Clinical signs appear rapidly because ethylene glycol is readily absorbed after ingestion.


Typically 3 stages are observed.

Stage I (30 minutes to 12 hours after ingestion): depression, incoordination, vomiting and increased respiratory rate. Make note that some animals could die within 9 hours, others may appear to improve but can deteriorate rapidly afterwards.

Stage II (12-24 hours after ingestion): we will observe an increase in respiratory rate and heart rate.

Stage III (24-72 hours after ingestion): acute renal failure. Decreased appetite, vomiting, excessive salivation, oral ulcers and decreased urine production.


Disease progression is not always this predictable though.

Blood tests will confirm renal insufficiency and metabolic acidosis. Urine test may show that oxalate crystals have formed. Some antifreeze products will fluoresce under a UV light, and we might be able to see the fluorescence in the mouth, the vomitus or urine.


It is imperative to consult a veterinarian as soon as we suspect ingestion. When less than 4 hours have elapsed since ingestion, even if there are no clinical signs, we can try to induce vomiting and administer a medication that will help to prevent absorption of the antifreeze. Inside an 18 hour window, an antidote can be injected intravenously but best results are obtained within 3 hours of ingestion, prognosis is than good. Prognosis is poor if renal insufficiency develops. Intravenous fluids are essentials to correct dehydration, improve organ perfusion, excrete ethelyne glycol, correct metabolic adidosis. Hemodyalisis and peritoneal dyalisis can be considered in severe cases of renal failure.