Antifreeze Poisoning in Dogs

Antifreeze is a serious hazard for curious pets who are attracted to its sweet taste, and is one of the most common causes of accidental death for dogs. Antifreeze is a widely used substance, and often people are unaware of its toxicity. This means that antifreeze is both commonly available and not always properly stored or disposed of. This allows pets to come in contact with it, whether on their owner’s property or that of a neighbor. All antifreeze should be kept out of pet’s reach, and any waste material contaminated with it should be stored in a lockable garbage can. Animals poisoned by antifreeze may appear drunk, urinate frequently, and vomit. Immediately see a veterinarian if your dog exhibits these symptoms. Many animals appear to recover before succumbing to fatal kidney damage.

• Lack of coordination
• Vomiting
• Excessive thirst
• Frequent urination
• Stupor
• Seizures
• Coma
• Swollen and painful kidneys

Consumption of antifreeze, some brands include:

• Prestone
• Peak
• Pentosin
• Generic antifreeze

Identifying ethylene glycol poisoning without the owner seeing or suspecting their dog encountering antifreeze is challenging - the symptoms may apply to a wide variety of conditions, and the poison acts quickly. However, there are a number of tests that together may indicate antifreeze poisoning if performed in a timely manner.

If it has been at least an hour since consumption of the antifreeze, a urine test will reveal an acidic pH, and microscopic inspection will show calcium oxalate crystals. This test is often performed with a simple “dipstick” approach, where a paper strip will change color to reflect the pH of the urine. Antifreeze often contains a fluorescent compound, so use of a black light to inspect the dog’s fur, mouth, and urine may indicate the animal has been in contact with the substance. Additionally, new commercially available kits can detect ethylene glycol in the blood serum and urine between an hour after consumption to 48 hours. These kits vary in their execution, but are done in the lab with a small sample of blood or urine, and are quick enough to be of diagnostic aid to save a pet’s life.

The success of treating antifreeze poisoning will depend on how quickly the pet arrives at the veterinarian’s office after ingesting the poison. If there is a possibility that there is still antifreeze in the stomach, the veterinarian may induce vomiting or pump out the contents of the stomach. This is usually only possible for an hour after consumption. After that, a medication called fomepizole can be administered to prevent the animal’s body from processing the ethylene glycol, and fluids given to help flush it out. This is usually sufficient to save a pet’s life if administered in the first 1-3 hours after poisoning, depending on the amount of antifreeze consumed and the circumstances. The acidity of the blood caused by the ethylene glycol already processed can be corrected with a sodium bicarbonate IV.

Unfortunately, if it has been more than 4 hours, the animal has likely processed the majority of the ethylene glycol into the compounds causing kidney failure by the time they arrive at the veterinarian’s office. Correction of fluid, electrolyte, and pH balance combined with administration of diuretics can sometimes be successful in saving a pet’s life, but most cases of renal failure have a poor outlook.

Antifreeze poisoning is a serious condition, but many dogs who are brought into their veterinarian soon after consuming the antifreeze make a full recovery. Timely diagnosis and treatment of the illness is key. Follow-up visits will be needed to check for kidney function and blood pH, but once the antifreeze is out of your pet’s body, they are on the road to recovery.

Make sure that any antifreeze should be kept away from animals and children at all times and properly disposed of in an out-of-reach place so that no one’s pet or child will have to undergo this ordeal.