Windshield washer fluid is a brightly-colored liquid made of methanol, a poisonous alcohol. Sometimes, small amounts of other toxic alcohols, such as ethylene glycol, are added to the mixture.
Some young children may mistake the fluid for juice, which can lead to accidental poisoning. Even small amounts can cause serious damage. This article discusses poisoning from swallowing windshield washer fluid.
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 your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.
Methanol (methyl alcohol, wood alcohol)
This poison is found in:
- Windshield washer fluid (used to clean automobile windows)
Symptoms of windshield washer fluid poisoning affect many different body systems.
Airway and lungs:
- Breathing difficulty
- No breathing
- Blindness, complete or partial, sometimes described as "snow blindness"
- Blurred vision
- Dilation (widening) of the pupils
Heart and blood:
- Low blood pressure
Skin and nails:
- Bluish-colored lips and fingernails
Stomach and intestines:
- Abdominal pain (severe)
- Liver problems, including jaundice (yellow skin) and bleeding
- Vomiting, sometimes bloody
Other symptoms may include:
Seek immediate medical help. DO NOT make a person throw up unless told to do so by Poison Control or a health care professional.
Before Calling Emergency
The following information is helpful for emergency assistance:
- Person's age, weight, and condition (for example, is the person awake or alert?)
- Name of the product (ingredients and strengths, if known)
- Time it was swallowed
- Amount swallowed
However, DO NOT delay calling for help if this information is not immediately available.
Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. 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. You can call 24 hours a day, 7 days a week.
What to Expect at the Emergency Room
The health care provider will measure and monitor the person's vital signs, including temperature, pulse, breathing rate, and blood pressure. Symptoms will be treated as appropriate. The person may receive:
- Activated charcoal
- Airway support, including oxygen, breathing tube through the mouth (intubation), and breathing machine (ventilator)
- Blood and urine tests
- Chest x-ray
- CT (computerized tomography, or advanced imaging) scan
- ECG (electrocardiogram, or heart tracing)
- Fluids through a vein (intravenous or IV)
- Medicine to treat symptoms, including antidotes to reverse the effect of the poison (fomepizole or ethanol)
- Tube through the nose to remove the remaining poison if the person is seen within 60 minutes of swallowing it
Because rapid removal of methanol is a key to treatment and survival, a kidney machine (renal dialysis) will likely be needed.
Methanol, the main ingredient in windshield washing fluid, is extremely poisonous. As little as 2 tablespoons (30 milliliters) can be deadly to a child. About 2 to 8 ounces (60 to 240 milliliters) can be deadly for an adult. Blindness is common and often permanent despite medical care. Multiple organs are affected by intake of methanol. Permanent organ damage may occur.
The ultimate outcome depends on how much poison was swallowed and how soon treatment was received.
Although many windshield washer fluids are a watered-down form of methanol, they can still be dangerous if swallowed.
Bluth MH, Pincus MR, Abraham NZ. Toxicology and therapeutic drug monitoring. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 24.
Nelson ME. Toxic alcohols. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 141.
Theobald JL, Kostic MA. Poisoning. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 77.
Review Date 2/12/2021
Updated by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.