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Dog in convertible

EVS Pet Urgent Pet Care is taking the month of April to brush up on our toxicology knowledge. Each of our staff members picked a topic to research and shared a presentation with the rest of the team. 

I was going to give this incredible case study on the dangers of rodenticides, but instead I will be discussing antifreeze toxicity! Why? you ask. Well Thursday morning I got into my car and I got a warning flash that my coolant was low.  My car was serviced and the coolant was refilled. 24 hours later I found my car had a puddle of coolant on the ground! In an absolute panic I made sure to clean all that off the street. You might be wondering why I was so freaked out. Well let me tell you… 

Antifreeze (coolant) is used to cool down a car’s engine to prevent it from overheating. While water is great to cool an engine down, it can also freeze! Thank you Chicago =( This is why the agent is mixed together with water to prevent freezing. The active ingredient in antifreeze is Ethylene Glycol. This substance is incredibly toxic! It also has a very sweet taste to it, which makes it all the more enticing to animals to lap it up. Companies try to mitigate this risk by making this liquid a bright color to make sure people know it is not just water, and some will even go the extra step to add a bittering agent to it. 

So what makes this product so toxic? As Ethylene glycol is metabolized it causes acute (sudden) kidney failure. When I say sudden I mean it. This product is typically completely metabolized within 16-24 hours! This means that if pets do not get help nearly immediately post ingestion it will likely be too late for a positive outcome. 

Another scary component is that it doesn’t take a large amount to cause this extreme organ damage. About 1 tsp /kg in dogs and 0.25 tsp/ kg in cats is enough to cause toxicity. 

What are the clinical signs? 

There are a few different stages of toxicity. 

Stage 1: 30 min - 12hr post ingestion: 

Typically these pets will look “drunk”. They can have a wobbly gait, vomiting, decreased appetite, decreased energy. 

Stage 2: 12hr-24hr post ingestion: 

Sometimes at this point pets will actually appear normal! Which oftentimes fools pet owners into thinking that they are in the clear. This cannot be further from the truth. 

Stage 3: 24 - 72 hr post ingestion: 

This is when the signs of renal disease will occur. These can include vomiting, diarrhea, painful abdomen (this is because the kidneys will become enlarged and painful), dehydration, lack of urine production. 

How can we treat this?  

We are lucky to have an antidote- Fomepizole! The downside is that it needs to be given very soon after ingestion for it to be effective. Approximately within 8 hours post ingestion for dogs, and 3 hours for cats. 

In addition to the antidote correcting all the other abnormalities caused from the toxicity need to be corrected as well. Hospitalization and aggressive supportive care is a pillar in treatment. 

The moral of the story is: 

Get your car in for routine maintenance. Make sure that your pets do not have access to these harmful substances. If you notice a car with fluid under it do not allow your pets near it! 

Most importantly, as there are some things outside of our control, if you even suspect that your pet might have been exposed to antifreeze, take them to your nearest veterinary clinic immediately!


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