Antifreeze poisoning
Engine coolant poisoning
Antifreeze is a liquid used to cool engines. It is also called engine coolant. This article discusses poisoning caused by swallowing antifreeze.
This article is for information only. DO NOT use it to treat or manage an actual poison exposure. If you or someone you are with has an exposure, call the local emergency number (such as 911) or the local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.
Poisonous Ingredient
The poisonous ingredients in antifreeze are:
- Ethylene glycol
- Methanol
- Propylene glycol
Where Found
The above ingredients are found in various antifreezes. They may also be used in other products.
Symptoms
Below are symptoms of antifreeze poisoning in different parts of the body.
AIRWAYS AND LUNGS
BLADDER AND KIDNEYS
- Blood in urine
- No urine output or decreased urine output
EYES, EARS, NOSE, AND THROAT
- Blurred vision
- Blindness
HEART AND BLOOD
- Rapid heartbeat
- Low blood pressure
MUSCLES AND JOINTS
NERVOUS SYSTEM
- Coma
- Convulsions
- Dizziness
- Fatigue
- Headache
- Slurred speech
- Stupor (lack of alertness)
- Unconsciousness
- Unsteady walk
- Weakness
SKIN
STOMACH AND GASTROINTESTINAL TRACT
- Nausea and vomiting
Home Care
Seek medical help right away. Do not make a person throw up unless poison control or a health care provider tells you to.
Use standard first aid and CPR for signs of shock or no heartbeat (cardiac arrest). Call 911 or the local poison control center for more help.
Before Calling Emergency
Have this information ready:
- Person's age, weight, and condition
- Name of product (as well as the ingredients, if known)
- Time it was swallowed
- Amount swallowed
Poison Control
The local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. This national hotline will let you talk to experts in poisoning. They will give you further instructions.
This is a free and confidential service. All local poison control centers in the United States use this national number. You should call if you have any questions about poisoning or poison prevention. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week.
You can also get online poison help now at
What to Expect at the Emergency Room
Take the container with you to the hospital, if possible.
Your provider will measure and monitor your vital signs, including temperature, pulse, breathing rate, and blood pressure. You may receive:
- Blood and urine tests
- Breathing support, including oxygen, a tube through the mouth into the throat, and attachment to a breathing machine (ventilator)
- Chest x-ray
- CT scan of the head (computed tomography)
- Electrocardiogram (ECG)
- Intravenous fluids (through a vein)
- Medicines to reverse the effects of the poison, such as Fomepizole or intravenous Ethanol
- Oral ethanol has been used historically as an effective alternative treatment for patients with methanol or ethylene glycol poisoning
- Tube placed down the nose and into the stomach (sometimes)
Dialysis (kidney machine) treatment may be needed during recovery. This need may be permanent if kidney damage is severe.
Outlook (Prognosis)
For ethylene glycol: Death may occur within the first 24 hours. If the patient survives, there may be little or no urine output for several weeks before the kidneys recover. Kidney damage may be permanent. Any brain damage that occurs also may be permanent.
For methanol: Methanol is extremely toxic. As little as 2 tablespoons (tbsp), 1 ounce (oz) or 30 milliliters (ml) can kill a child, and 4 to 16 tbsp., 2 to 8 oz or 60 to 240 ml can be deadly for an adult. The outcome depends on how much was swallowed and how soon appropriate care was given. Vision loss or blindness may be permanent.
Permanent damage to the nervous system may occur. This can cause blindness, decreased mental functioning, and a condition similar to Parkinson disease.
Keep all chemicals, cleaners, and industrial products in their original containers and marked as poison, and out of the reach of children. This will reduce the risk for poisoning and overdose.
References
Nelson LS, Calello DP. Acute poisoning. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 96.
Nelson ME. Toxic alcohols. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 136.
Seifter JL. Acid-base disorders. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 104.
Version Info
Last reviewed on: 4/8/2025
Reviewed by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
