Neurologic Symptoms in Canines From Ethylene Glycol Toxicity

Consuming just a small amount of antifreeze can kill your dog.
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Ethylene glycol is the primary component of most antifreeze, making up approximately 95 percent of the product. It's also found in rust remover and other solvents. Because of its sweet taste, pets might lap up spilled antifreeze, with often fatal results. Since the initial symptoms of ethylene glycol poisoning in canines are neurological, getting your dog to the vet immediately if he shows these signs can save his life.

Antifreeze Toxicity

The minimum lethal dose of undiluted ethylene glycol for dogs is 4.4 milliliters per kilogram of the animal's weight, according to the "Merck Veterinary Manual." Besides early veterinary treatment, a dog's prognosis depends on just how much of the substance he consumed. The dog's body quickly absorbs ethylene glycol into the digestive tract, where it metabolizes to oxalic acid. It then joins with calcium, forming crystals. These crystals head to the kidneys, where renal failure ensues. Oxalic acid can also cross the blood-brain barrier, causing neurological symptoms and death.

Neurological Symptoms

If your dog lapped up some antifreeze or another product containing ethylene glycol, the initial symptoms of poisoning generally appear within a half-hour. The dog becomes ataxic, meaning he is uncoordinated, staggering about as if he were drunk. He could knuckle over when walking. Your dog might also experience seizures, muscle twitching and head tremors, or become extremely excited. He must receive treatment in the early stages of ethylene glycol poisoning, before his kidneys are severely damaged.

Other Symptoms

Other early symptoms of antifreeze poisoning include vomiting, excessive thirst and frequent urination. After about 12 hours, the dog's heart starts beating rapidly, and the dog exhibits rapid respiration. His body temperature drops and his pupils constrict. Roughly 24 hours after consumption, he experiences diarrhea and might throw up bright green vomit. Dogs reaching this stage are unlikely to survive.


If your vet sees your dog immediately after consuming ethylene glycol, your vet might induce vomiting. Ethylene glycol absorbs rapidly, so vomiting isn't useful after a few hours have passed. The vet may test your dog's blood for ethylene glycol levels if ingestion was less than 12 hours prior. After that, blood level readings aren't accurate. She'll conduct ultrasound tests to determine kidney and liver abnormalities. Your vet might also administer activated charcoal to soak up the substance and flush out the stomach. Your dog might receive intravenous fluid therapy to flush out the kidneys. If your dog does survive, it could take weeks to recover, and he might require kidney dialysis for a certain period.