FieldDxEthylene Glycol ToxicosisClinical signs, differential diagnosis, treatment and prevention.
Overview
A common and often fatal poisoning from ingesting antifreeze or other ethylene-glycol-containing products. Ethylene glycol ingestion; its metabolites (glycolic and oxalic acid) cause severe metabolic acidosis and acute kidney injury.
Clinical signs
- Dogs, 30 minutes to 12 hours after ingestion: vomiting, polydipsia, polyuria.
- Depression, stupor, ataxia, knuckling and reduced proprioception.
- A brief apparent recovery about 12 hours after ingestion.
- Dogs, 36-72 hours: oliguric acute kidney failure progressing to anuria.
- Enlarged, painful kidneys.
- Tachycardia and tachypnoea.
- Anorexia, vomiting, diarrhoea, oral ulcers and salivation.
- Lethargy, then seizures, coma and death.
Predisposing factors
- Dogs and cats are most often affected.
- Antifreeze tastes sweet and is readily drunk.
- Poor storage, use and disposal of the product.
- Concentrated preparations are widely available.
Treatment
- Intravenous fluids at calculated replacement volumes.
- Fomepizole (4-methylpyrazole) is the treatment of choice in dogs: 20 mg/kg IV initially, then 15 mg/kg IV at 12 and 24 hours.
- Cats need higher rates: 125 mg/kg initially, then 31.3 mg/kg at 12, 24 and 36 hours.
- Ethanol as an alternative where fomepizole is unavailable.
- Sodium bicarbonate for severe metabolic acidosis below pH 7.2.
- Dextrose for hypoglycaemia and calcium gluconate for hypocalcaemia.
Drugs mentioned: Ethanol Fomepizole Sodium Bicarbonate
Prevention
1. Store and dispose of antifreeze properly. 2. Bittering agents have been added to antifreeze in the United States since 2012. 3. Keep animals out of vehicle maintenance areas.
Source
MSD Veterinary Manual — Ethylene Glycol Toxicosis in Animals (accessed 2026-07-31)
Condensed and attributed, never reproduced whole. Open the full entry in the app.