Antifreeze poisoning in dogs and cats

More than ten thousand dogs and cats die from antifreeze poisoning every year. The toxic compound in antifreeze is called ethylene glycol and it is commonly found in many garages and driveways around the country. EG poisoning occurs year round as many people flush their radiators both spring and fall.

In cold weather climates it is slightly more common because EG does not freeze and can serve as a source of fluids for outdoor dogs. Radiator leaks are the most common source of poisoning in both dogs and cats.

Ethylene glycol is sweet to the taste and appeals to both dogs and cats. It does not take much to create a serious problem - especially in cats. Cats are four times as susceptible as dogs and as little as one to two teaspoons can be deadly for cats. It takes only 3 to 4 tablespoons to kill a medium size dog.

I'll never forget a call I got late one weekend from one of our baby sitters when I practiced in Montana. She had gotten home from an evening at the local bars only to discover that her own dog appeared drunk. She considered this slightly amusing until her dog fell down the steps and came up limping. Lucky break for the dog.

She called me to ask about the limp and the conversation revealed the "looked drunk" precursor to the fall down the steps. I was about to tell her to go to bed and come by in the morning when she sobered up, but the drunk comment bothered me even in my sleepy torpor. Before she hung up I asked her if she had changed the radiator fluid in her car lately. She replied that she was planning on doing just that soon because her radiator leaked like an SOB all over the garage.

EG is metabolized very rapidly and dogs indeed appear drunk as little a 30 minutes after ingestion. The liver and kidneys are involved with processing this toxin and it's the lasting, sometimes irreversible, damage to the kidneys that is fatal to dogs and cats. The key to successful treatment is to catch it early and stop the conversion of EG to the toxic metabolites that do the damage to the kidneys.

If you diagnose and treat within 8 to 12 hours in dogs the outcome is fair to good unless they have consumed too much. With cats the prognosis is only fair to poor if they are showing clinical signs and you intervene early.

Ironically, one of the treatment protocols involves intravenous ethanol. Ethanol is the key ingredient in booze and if you are working in a mixed animal practice in Montana chances are you have some of this substance lying around.

 

In the case of my baby sitter some of my own prized vodka did the trick along with fluid therapy to restore her dog's acid base balance. We sent them home the next day and the only lasting damage was the limp from the tumble down the steps. We were lucky to have caught it early enough. If she had waited until the next morning it would have been too late. Her dog would not have appeared drunk anymore. He may have started to show signs of kidney failure like excessive drinking and urinating and it would have probably been too late to help.

There are so called "safe" antifreeze products around these days that use propylene glycol instead of ethylene glycol as the active ingredient. These products are not completely safe - only less toxic. The EG containing products are still more common though. If you have any of this stuff in the garage make sure it's in safe containers stored out of the reach of pets or kids. I happen to have a five gallon jug of EG in my solar room for use in my solar collectors. If your kids have a portable basketball hoop it's possible that the stuff in the base contains EG, too. 

My advice would be to leave the radiator work to the mechanic and not have any of the stuff around. In any case, make sure your car's cooling system is working properly and your garage floor is clean. If you do have a spill use some cat litter to absorb the mess and clean up completely. You don't want cats licking the floor even after you've cleaned it up.       

Comments

[Folding Dog Stairs]

Very nice post.I think California passed a law that requires an additive to antifreeze that makes it very bitter, so animals won't like/drink it. Seems like a good idea.

[Bonnie]

I think that's what happened to my cat about 5 years ago. He was an indoor cat, but got out when a neighbor visited (I didn't know this until much later). He was only gone a couple of days when I got a call from the local animal shelter (I had registration info on his collar). I thought they were calling to say they found him, which they did... but he was dead. Just 3 houses away in a neighbor's back yard. Maybe it was some other kind of poison, but antifreeze is so common and so appealing, it's my number-one suspect.
I think California (where I live) passed a law that requies an additive to antifreeze that makes it very bitter, so animals (and kids) won't like/drink it. Seems like a good idea.