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Can You Kill Rats With Antifreeze?

(Last Updated On: June 4, 2022)

Antifreeze is a toxic substance, often used as an ingredient in brake fluid and windshield wipers.

Some people use it to eliminate pests and unwanted animals from their homes and yards. While it’s poisonous to mammals, using antifreeze as rat poison may not always be advisable.

You can kill rats with antifreeze, as ethylene glycol is highly toxic.

It can cause vomiting, loss of consciousness, seizures, and death when ingested. However, using antifreeze as pest control has risks since it can poison cats, dogs, and young children.

That doesn’t mean you can never use antifreeze for pest control. You just need to exercise caution when you do. Let’s explore how antifreeze kills rats and how to use this poisonous bait.  

Will Rats Drink Antifreeze And Die?

Antifreeze contains ethylene glycol, which is a known toxin. However, rats may not drink antifreeze or drink enough to be effective.

According to The Canadian Veterinary Journal, rats dislike the taste of antifreeze. In their experiment, researchers determined that the higher the concentration of antifreeze, the less the rats drank.

However, antifreeze is a common DIY rodent poison, despite not being made specifically for rodent control. Commercially available rat poisons, traps, and baits are often more reliable and safer.

Ethylene Glycol

The main ingredient in antifreeze is ethylene glycol.

Adding ethylene glycol to a solution lowers the freezing point, ensuring that the solution doesn’t freeze. It’s colorless, odorless, and sweet-tasting.

Ethylene glycol is found in other fluids where freezing is not preferable. So, you’ll find it in many de-icing products. It’s most commonly found in brake fluid, wiper washer fluid, and coolant.

Ethylene glycol can also be found in everyday products at lower concentrations, including cosmetics, ballpoint pens, and paints.

Ethylene glycol lowers freezing points because it can absorb water. However, this is also what makes it highly toxic. Ingesting ethylene glycol leads to ethylene glycol poisoning.

When ingested, ethylene glycol affects the nervous system, metabolic processes, and kidneys.

Ethylene Glycol Poisoning

Antifreeze has been known to kill animals and humans through accidental poisoning, causing a slow and painful death. As many as 5,000 cases of ethylene poisoning happen per year in the U.S. alone.

Symptoms of ethylene glycol poisoning include the following.

  • Intoxication
  • Vomiting
  • Abdominal pain
  • Loss of or decreased consciousness
  • Headaches
  • Seizures

What Does Antifreeze Do To Rats?

Antifreeze affects rats the same way that it affects humans and other animals.

You’ll observe the same symptoms of ethylene glycol poisoning. This will include shutting down the nervous system and blocking the kidneys.

However, antifreeze isn’t just toxic to rats. It’s toxic to any other animal, including humans. If you have pets or small children, avoid using this pest control solution.

Does Windshield Washer Fluid Kill Rats?

Windshield washer fluid can kill rats because the fluid contains either ethylene glycol or methanol, both known toxins.

Ethylene glycol, being the main ingredient in antifreeze, will kill rats. It’s present in windshield wiper fluid to ensure that the fluid remains liquid at low temperatures.

Other than ethylene glycol, some formulas also use methanol to lower the fluid’s freezing temperature. Methanol and ethanol have similar properties.

Both are poisonous, can cause the same symptoms when ingested, and smell similar. Like ethanol, methanol can also attract rodents and kill them.

Even ingesting 10 ml. of methanol can cause permanent blindness. In the EU, methanol is banned for use in windshield wiper fluid. Instead, ethanol is used, much like in antifreeze.

will rats drink antifreeze and die?

How Fast Does Antifreeze Kill Rats?

Ethylene glycol is a slow-acting toxin. So, it may take a few days for antifreeze to kill a rat.

How Do You Kill Rats With Antifreeze?

Antifreeze should only be used as rat poison as a last resort.

Other rodent control options, like rat bait and traps, are safer and more effective. However, if you do need to use antifreeze, there are a few methods that you can choose from.

Find An Area To Lay The Poison

It is important to find the right spot to place the antifreeze.

Remember that antifreeze will kill anything that ingests it. That’s why it is important not to just look for a spot where there are rats. Seek out a location that children and pets can’t access.

Likewise, ensure that wild animals cannot get to it either. Otherwise, you may have to dispose of other dead animals on your property.

Prepare A Container

Putting the antifreeze in a container is a good way to ensure that rats get easy access but that bigger animals do not.

Containers can include pails, tall cups, or Tupperware. If the container is deep enough, a rat will have a hard time getting out, making it more likely for the rat to drink the antifreeze.

Secure the container so that it doesn’t topple over. You can use blocks or cardboard to hold it in place.

Wear Protective Equipment

Antifreeze can cause irritation when it comes into contact with the skin.

Wear gloves every time you handle antifreeze. Skin exposure is not as dangerous as ingesting antifreeze, but it’s best to stay safe.

When handling antifreeze, it also helps to wear clothing that covers your arms, legs, and eyes. If you get antifreeze on your skin, wash it immediately with soap and water.

Prepare Your Bait

Next, prepare the bait. Antifreeze does not smell like anything, and rats will not want to take a sip. You will need to mix the antifreeze with something that smells tasty to rats.

No matter what method you choose, cover the bait with cardboard. In this way, rats will feel less wary about their surroundings and find the bait more readily.


Soaking bread in antifreeze is a common way to create an antifreeze rat bait.

Add bread to a bowl of antifreeze and allow the bread to soak up the product. Then, place the bread in the container you chose. Place the container in an area where rats frequent.


Another way you can make antifreeze smell nice is by mixing it with coke. Take ½ cup of coke and add a few tablespoons of antifreeze. Then, place the mixture in your container and set it up in areas where you see rats.


This method uses a bottle to keep pets out. While the bottle can stop nosy animals from drinking the antifreeze, there is no guarantee that a curious cat or dog will knock over the bottle anyway to get to the antifreeze.