Antifreeze Poisoning in Dogs: Symptoms, Treatment, and Prevention

Antifreeze is an ever-present danger to our pets, with exposures in dogs increasing during the cold-weather months.   

Ethylene glycol is the most common ingredient in automotive antifreeze, and even small amounts can be lethal to dogs.  

Antifreeze used for RVs, boats, cabins, and other equipment often contains propylene glycol instead of ethylene glycol. While the names sound similar, they pose very different risks if ingested. Therefore, if your dog ingests antifreeze, it’s important to determine the type before treatment begins.  

For antifreeze containing ethylene glycol, pet parents must stay vigilant about preventing access to automotive fluids, leaking bottles, or pans used in car maintenance.  

If you suspect your dog ingested any type of antifreeze, contact your veterinarian or Pet Poison Helpline at 1-855-764-7661 immediately. 

What Is Antifreeze Poisoning in Dogs?

Antifreeze poisoning occurs when a dog ingests ethylene glycol or another toxic form of antifreeze. 

• Typically, there is a suspicion that a pet had access to, or was near, a puddle of antifreeze or fluids from automobiles. When a dog ingests ethylene glycol, symptoms often appear within a few hours after the ingestion and may include vomiting, increased thirst and urination, and ataxia (lack of coordination when walking).   

• Additional symptoms that may develop over the next 8 to 48 hours include panting, seizures, and coma.  

If you suspect your pet ingested ethylene glycol, call the Pet Poison Helpline at 855-764-7661 or seek emergency veterinary care immediately. Do not wait for symptoms to appear, as a delay in treatment often results in death.   

Ethylene glycol is an odorless, sweet-tasting liquid. After ingestion, dogs may vomit and appear disoriented or have difficulty walking. Once metabolized, ethylene glycol causes acute kidney failure, which is fatal without early treatment. Therefore, it’s extremely important to begin treatment before kidney damage develops. 

Common sources of ethylene glycol include: 

• Antifreeze used in automobile engines 

• Windshield wiper fluid and deicing agents 

• Brake fluid 

• Paint and ink   

The amount of ethylene glycol varies by product. While antifreeze is the most concentrated and dangerous (typically 50–100%), other products usually contain lower concentrations and require larger ingestions to cause poisoning.   

Symptoms of Antifreeze Poisoning in Dogs

Within 12 hours of ingestion: 

• Vomiting 

• Ataxia (incoordination when walking) 

• Lethargy  

• Inability to stand 

• Increased drinking and urination 

After 12 hours or longer of ingestion: 

• Tremors 

• Seizures 

• Coma 

• Panting 

• No urination 

My Dog Ingested Antifreeze. Now What?

If you suspect or know your dog ingested antifreeze or another product containing ethylene glycol, call Pet Poison Helpline (855-764-7661) or seek emergency veterinary care immediately. Even a small amount can be deadly, and the sooner treatment is started, the better the outcome.   

If possible, locate the product container. The more information that can be obtained regarding the product, including the brand, ingredients, and concentration, the more accurate an assessment can be made as to whether treatment is necessary and what kind.   

For the best outcome, treatment should begin within eight hours of ingestion.   

Treatment of Antifreeze Poisoning in Dogs

Two antidotes are available for antifreeze poisoning: ethanol and fomepizole.   

If either antidote is started within eight hours after ingestion and before significant symptoms or blood work abnormalities develop, prognosis is good.  

Prognosis declines sharply if treatment begins more than eight hours after ingestion or if  diagnostic tests show kidney damage or significant symptoms are present. 

When treated promptly and successfully, dogs who recover typically have no long-term effects.   

Prevention of Antifreeze Poisoning in Dogs

• Keep dogs out of garages, sheds, or areas where antifreeze is stored. 

• Store all chemicals securely, especially around pets (chemicals are also dangerous to cats).  

• Avoid ethylene glycol-based ice melts. Instead, opt for pet-safe ice melts such as Safe Paw Pet-Safe Ice Melt or Natural Rapport Pet-Safe Ice Melt. 

If your dog is able to paw open cabinets, consider using the MyPet Safety Cabinet Latch, and ensure that all products are stored far enough away from easy access. 

• Immediately clean up any spills of antifreeze or other automotive liquids. 

• Watch for suspicious puddles in driveways or garages and clean them promptly. Keep pets away from these areas to avoid accidental ingestion.