Ethylene glycol is the primary ingredient in many brands of antifreeze. It is extremely toxic to animals and people alike, a fact that is compounded by its slightly sweet taste. It is odorless and colorless and often irresistible to dogs when they find it in a puddle in the garage or driveway. Propylene glycol is an effective alternative to ethylene glycol, and the FDA has recently labeled propylene glycol safe. Using a product with propylene glycol is the best thing you can do to prevent poisoning in your pets. This limits your pets exposure to this potentially devastating toxin, but obviously does not eliminate it completely as guests and neighbors may still be using antifreeze containing ethylene glycol. Ethylene glycol is especially dangerous since it only takes about 3oz to poison a medium-sized dog.
There are three stages of ethylene glycol poisoning, with the first stage lasting for approximately 12 hours and consisting of apparent intoxication including incoordination and vomiting. Some animals develop nystagmus (abnormal movement of the eyes). The second stage occurs between 12-36 hours and consists of increased heart rate, respiratory rate and blood pressure. Muscle spasms, tremors, seizures and heart failure can also occur during this stage. Death occurs most commonly during stage two. The final stage of toxicity occurs between 24-72 hours and consists of kidney failure. Decreased or no urination, increased drinking, excessive urination or red blood cells in the urine can all indicate kidney disease.
If it is possible that your dog could have ingested ethylene glycol and he/she exhibits any of these symptoms it is imperative that you get him/her to the veterinarian immediately. If it is determined that your pet has ingested this toxin within the last several hours they will likely be given an injection to make them vomit up any toxin that may remain in their stomach. Activated charcoal may then be administered orally. This helps to bind any toxin that remains and flush it from the GI tract. An appropriate antidote to ethylene glycol is also administered, which binds to the toxin that has already made it into the blood stream. An IV catheter and fluids are critical in flushing as much of the already absorbed toxin from the blood as possible. Symptomatic treatment and supportive care are critical over the following days.
Immediate identification and treatment of the ingestion offers your pet the best prognosis for a full recovery. Unfortunately, very small amounts of absorbed ethylene glycol can cause severe kidney damage, so if the ingestion goes unnoticed for several hours some degree of kidney disease will likely result.