Antifreeze, aka, ethylene glycol, is a colorless, odorless, sweet-tasting chemical. It is poisonous if swallowed by humans and our pets.

IMPORTANT: This article is for informational purposes only. DO NOT use it to treat or manage an actual antifreeze poison incident.

If you suspect your dog has consumed any amount of Antifreeze, even the smallest amount, call your emergency vet immediately. You may also contact the ASPCA Poison Control at 888 426-4435 or Pet Poison Helpline at 855-764-7661.

DO NOT WAIT!!! Every single second counts when it comes to anti-freeze poisoning. 

infographic of the 3 stages of anti-freeze poisoning in dogs

Stages and symptoms of antifreeze poisoning in dogs

According to the Animal Poison Control Center, there are 3 stages of antifreeze poisoning.

Stage one of antifreeze poisoning occurs 30 minutes to 12 hours after ingestion. Watch for these symptoms: 

  • Signs of walking drunk
  • Excessive thirst and urination
  • Drooling
  • Vomiting
  • Seizures

Stage two of antifreeze poisoning occurs 12 to 24 hours after ingestion. Watch for these symptoms:

  • Clinical signs seem to “resolve” when in fact more severe internal injury is still occurring

Stage three of antifreeze poisoning occurs 36 to 72 hours after ingestion. Watch for these symptoms:

• Loss of appetite, not eating

• Drooling

• Vomiting

• Severe Acute Kidney Failure

• Halitosis/Bad Breath (secondary to kidney failure)

• Depression

• Lethargy

• Coma

• Seizures

small dog looking sad out window

Antifreeze and your dog – questions answered by Vets

Dr. Alex Schechter and Dr. Anna Massey have answered several of my questions about Antifreeze and Dogs. I hope this helps you understand the dangers and prepare for the “just in case” scenario… because I pray this never happens to anyone!

Q: What should a dog owner do if they suspect their dog has ingested antifreeze?

Dr. Alex Schechter:

A: Less than half of a teaspoon of antifreeze can be a severe health hazard for a dog. The poisoning affects the gastrointestinal tract, liver, brain, and, leading to acute kidney failure.

If you suspect the pet has ingested antifreeze, immediately seek veterinary attention.

Antifreeze starts forming toxic metabolites quickly, and delay in seeking a vet’s attention can be deadly. 

Dr. Anna Massey:

A: Immediately call the ASPCA Poison Control 888-426-4435 or Pet Poison Helpline 855-764-7661 as you are preparing to bring your dog to the closest 24/hr ER veterinary facility.

Be advised there is a consultation fee associated with calling these poison control centers and you will be given a case number your veterinarian can refer back to once you arrive at the veterinary office. 

Q: Other than the obvious to reach out to their vet, is there anything an owner can do at home for their dog while waiting to talk with a vet?

Dr. Alex Schechter:

A: Yes, there are a few things an owner can do at home for their dog if they have antifreeze poisoning.

  • First, it’s important to contact a veterinarian as soon as possible.
  • Antifreeze poisoning can be fatal, and the vet will be able to provide the best advice on how to proceed with treatment. 
  • In the meantime, if your dog vomits, collect the sample for testing.
  • Keep your pet’s medical history handy.
  • Also, try to identify the toxin and how your dog came into contact with it so you can provide as much information to your vet; you can have the packaging of the products on hand for reference.
  • You should also monitor your dog closely, looking out for signs of poisoning. 

Dr. Anna Massey:

A: Unless otherwise recommended by the veterinary toxicologist on the phone, do not attempt to induce vomiting in your dog at home, as this can be potentially dangerous and lead to complications.

Keep a close eye on your dog so that you can report any symptoms or changes in their condition to the veterinary staff.

The signs you may see are dependent on how much was ingested and how long it has been since ingestion occurred. Weakness, acting “drunk,” vomiting, twitching, and lethargy may initially be seen. As the intoxication progresses, seizures and even coma can occur. 

Q: What can they expect once they arrive at their vets office?

Dr. Alex Schechter:

A: Vets often ask for the symptoms, test stool or vomit, and also conduct a thorough urinalysis and chemical blood profile. The treatment is done based on diagnosing the poisoning and the dog’s medical history. 

Vets try to prevent the toxin from metabolizing; usually, antidotes 4-MP and Fomepizole are used.

Also, the pet will be hospitalized for observation and administration of 4-MP for 36 hours.

IV fluids and additional supportive care are also provided to treat electrolyte imbalances, vomiting, dehydration, and nausea. 

Dr. Anna Massey:

A: Once they arrive at the veterinary hospital, owners can expect that their dog’s vitals will be taken, and, depending on when the ingestion of the antifreeze occurred, their dog may be given a drug to induce vomiting.

Baseline blood work to check kidney values and electrolytes will also likely be recommended.

Have your poison control case number readily available in case the veterinarian needs to touch base with the toxicologist.

The veterinarian will also likely discuss administering an antidote, either “4-MP” or ethanol. These drugs help prevent the metabolism of the toxin in antifreeze and aid in its excretion from the body via urine. Depending on the timing of ingestion, these drugs may or may not be helpful or indicated.

Other treatments that will likely be discussed are intravenous fluids and medications to treat any seizures or electrolyte abnormalities.

Your veterinarian will also potentially discuss hemodialysis (the use of a special machine to filter and “clean” your dog’s blood) as a treatment option. 

Q: Is there a certain time frame to consider?

Dr. Alex Schechter:

A: For the best prognosis, the pet needs to be treated within the first 5 hours, and it should not be delayed beyond 8-12 hours of ingestion. If the pet shows symptoms of kidney damage, the prognosis is abysmal.

So, if you suspect or witness any sign of poisoning, your pet may have ingested antifreeze, rush to the nearest veterinary emergency.  

Dr. Anna Massey:

A: Yes! The toxin in antifreeze is ethylene glycol and itself can cause GI and neurologic signs, but it is the breakdown of ethylene glycol that can cause kidney damage and more serious neurologic effects. Therefore, the sooner you can seek treatment, the better.

The goal is to prevent the ongoing metabolism of the toxin, and this should be done ASAP since this starts happening within the hour of ingestion. The antidotes can be given within 3 hours of ingestion and still likely help with the ongoing metabolism of the toxin.

Q: What is the survival rate of antifreeze poisoning?

Dr. Alex Schechter:

A: The survival rate probability is highest if the pet gets vet care within the first 5 hours of the ingestion. However, if the treatment is administered within 8 to 12 hours, it can be lifesaving.

Dr. Anna Massey:

A: Survival rates ultimately depend on how quickly after ingestion the dog was able to receive veterinary care, but mortality rates can be as high as 70%.

If treatment is initiated quickly, survival rates can be much higher. If available, hemodialysis should be considered, since nearly 100% of the ethylene glycol and its metabolized compounds can be removed with one treatment.

Later on, when kidney damage has occurred, dogs may need multiple hemodialysis treatments and the prognosis is much more guarded.

Q: Anything else a dog owner needs to know about Antifreeze and dogs?

Dr. Alex Schechter:

A: It’s essential to keep your dog away from any sources of antifreeze, such as car radiators. Be aware of possible sources of antifreeze and ensure to keep it in a sealed container.

Make sure to store any antifreeze containers in a secure location where your dog won’t be able to get to them.

Also, choose antifreeze with Propylene glycol, as it is a safe option as per the U.S. Food & Drug Administration. 

In some instances of antifreeze poisoning that I have handled, I have seen that immediately after ingestion, these blood tests won’t usually show anything for the metabolization of ethylene glycol as to metabolize and create toxic byproducts the chemical takes time.

Hence it is always suggested to rush to an emergency clinic where the diagnosis can be made using test strips. The test should be conducted between 1 and 11 hours after the ingestion

Dr. Anna Massey:

A. Not a lot of hospitals offer hemodialysis, but you can bring your dog to a veterinary ER for initial stabilization and antidote administration, then consider transfer to a facility for hemodialysis, if available.

The biggest concerns with antifreeze toxicity are kidney failure, seizures, and coma. The most important thing is to seek veterinary treatment ASAP.

If you are unsure if your dog has ingested antifreeze or not, there are blood tests that can be done at your vet’s office to verify. These tests may not detect antifreeze after 2-3 days post-ingestion. 

Another important point is that the toxin in antifreeze is also found in some paints, adhesives, wood stains, and de-icers, and it only takes ingesting a small amount to cause toxicity.

Ethylene glycol in your house

According to MedlinePlus, you can find ethylene glycol in many household products, including:

  • Antifreeze
  • Car wash fluids
  • De-icing products
  • Detergents
  • Vehicle brake fluids
  • Industrial solvents
  • Paints
  • Cosmetics

Note: This list is not complete. It became obvious after learning about the death of two dogs after their owner was cleaning up a broken snow globe. Of all things, no one would ever suspect such an innocent decoration to be so dangerous.

This snow globe story is what prompted me to dig deeper into Antifreeze poisoning.

About the Vets

Alex Schechter

Alex Schechter, DVM, is a renowned vet, pursuing a career in animal medicine, Dr. Schechter earned his Doctorate in Veterinary Medicine from Michigan State University College of Veterinary Medicine. 

He has completed advanced training in Small Animal Medicine and Surgery at BluePearl Veterinary Partners in Manhattan. Experiencing great success, he remained at BluePearl afterward as a Senior Emergency Clinician.

Dr. Schechter joined the team at Pure Paws of Hell’s Kitchen. He is currently working in his veterinary hospital, Burrwood Veterinary, driven by his love for animals & offering pet care services, including urgent care, wellness care & personalized care for pets. 

Anna Massey

Dr. Anna Massey, Director of Emergency and Critical Care and staff ER veterinarian at one of the largest tertiary referral/specialty small animal veterinary hospital with over 17 years of experience as an emergency small animal veterinarian.

I graduated from the University of Pennsylvania School of Veterinary Medicine in 2005 and have been a practicing veterinarian in emergency and critical care ever since. I currently head up one of the largest and busiest ER and ICUs for small animals in the country at Red Bank Veterinary Hospital in Tinton Falls, NJ, part of the NVA-Compassion First Hospital Network.

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About the Author

Debi McKee

Debi McKee is the expert behind Rescue Dogs 101 where she guides you in your journey of adopting and raising a rescue dog every step of the way. She is a mom of 3 human kids and 4 dogs and volunteers for a local dog rescue and Humane Society. Click here for more about Debi and her passion for helping you and your dog.

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