Public Health Concerns
At the start of winter, many people pay closer attention to their vehicles and try to ensure that all of their automotive liquids are fresh and in working order. One of the liquids most commonly attended to is antifreeze, a coolant used to keep vehicle engines from overheating. But antifreeze is among the deadliest of liquids when ingested by a small animal.
Why would an animal want to drink antifreeze?
One of the main ingredients in most brands of antifreeze is ethylene glycol, a syrupy liquid that has an inviting aroma and a sweet flavor. If a particular brand of antifreeze contains ethylene glycol as one of its ingredients, the entire mixture will taste and smell sugary, which will attract not only domestic pets like dogs and cats, but also wild animals and, in some cases, children. Pets usually gain access to antifreeze when some of the liquid has been spilled or has leaked from a vehicle onto a driveway or the floor of a garage. Unfortunately, a dog or cat that gets a taste of antifreeze can often lap up a lethal dose in a very short amount of time.
There are brands of antifreeze available now that add a bittering agent to ruin the sweet taste, and several states even require it; Texas, however, is not one of them, nor is our neighboring state of Oklahoma (although New Mexico is). Other brands have replaced ethylene glycol with propylene glycol, which is a less toxic ingredient. The problem is that these brands are typically more expensive, which means that they have yet to gain widespread popularity.
What happens when a pet ingests antifreeze?
Ethylene glycol crystallizes when it reaches an animal's kidneys, and it then ruptures the kidney cells. These crystals also inhibit the animal's ability to urinate, and an animal that goes untreated can enter into total kidney failure within four hours. There are ways to prevent the antifreeze from crystallizing in the kidneys, but preventative measures must be taken almost immediately. And the toxic dose of antifreeze is very small: as little as one teaspoon can kill a regular-sized cat, and three tablespoons can kill a 22-pound dog.
What are the symptoms of antifreeze poisoning?
The symptoms depend heavily on how much of the liquid the animal ingests. If she ingests only a small amount, it may take several hours for you to notice any change in her behavior. If, however, she ingests a considerable amount of antifreeze, symptoms may appear in as few as 30 minutes. The following are common symptoms of antifreeze poisoning:
First of all, if you see your pet lapping up, sniffing, or seeming even remotely interested in a pool of brightly colored liquid (most commercial antifreezes contain bright dyes that make them appear fluorescent green, blue, or red), pull her away immediately and contact your veterinarian. You need to get your pet to her regular veterinarian or an emergency facility as quickly as possible. Antifreeze poisoning is an emergency.
What will my veterinarian do?
Strange as it sounds, the best treatment for antifreeze poisoning is usually to get an animal drunk. (Don't ever attempt to do this yourself; alcohol is toxic for pets also, unless given the proper way and in the proper amount.) Depending upon the amount of antifreeze the animal has consumed, a vet will probably hospitalize your pet, start her on IV fluids, and get her to ingest a substance with high alcohol content. The reason for giving an animal drinking alcohol is that when a dog or cat is drunk, the body would rather concentrate on getting rid of the alcohol than the antifreeze. As stated above, when antifreeze crystallizes in the kidneys, the body can no longer break the substance down, and the animal quickly goes into kidney failure. If the body is busy taking care of drinking alcohol in the system, then it doesn't get a chance to work on the antifreeze until after the liver has metabolized it into a less harmful substance.
It usually takes anywhere from 36 to 48 hours to determine whether a pet will survive antifreeze poisoning, and your vet may want to keep your pet a few additional hours just to make sure that the incident causes no complications. Also, be prepared for your vet to want to do lab work in order to monitor your pet's kidneys and ensure that they haven't undergone severe damage. At the SAEC, we perform initial, baseline bloodwork on antifreeze toxicity patients, and then we repeat the bloodwork at regular intervals during the pet's hospital stay.
Some final things to consider:
Ethylene glycol is most commonly found in antifreeze, but there are other sources as well: windshield de-icing fluids, hydraulic brake fluid, developing solutions for film photography, paints, solvents, and even winterizing liquid that is sometimes poured into pipes and toilet bowls. Make every effort to keep your pet away from areas of your home where chemical agents are stored—storage buildings, garages, closets, etc.
Pet food, pet treats, and pet toys are specially formulated to be safe for pets. If you see your pet ingesting anything that isn't specifically meant to be eaten by dogs or cats, play it safe and contact your veterinarian. You never know when something that seems harmless might be fatal.