Boric acid is a dangerous poison. Poisoning from this chemical can be acute or chronic. Acute boric acid poisoning usually occurs when someone swallows powdered roach-killing products that contain the chemical. Boric acid is a caustic chemical. If it contacts tissues, it can cause injury.
Chronic poisoning occurs in those who are repeatedly exposed to boric acid. For example, in the past, boric acid was used to disinfect and treat wounds. People who repeatedly received such treatment got sick, and some died.
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 center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.
Boric acid is found in:
- Antiseptics and astringents
- Enamels and glazes
- Glass fiber manufacturing
- Medicated powders
- Skin lotions
- Some paints
- Some rodent and ant pesticides
- Photography chemicals
- Powders to kill roaches
- Some eye wash products
Note: This list may not be all inclusive.
The main symptoms of boric acid poisoning are blue-green vomit, diarrhea, and a bright red rash on the skin. Other symptoms may include:
- Coma (lack of responsiveness)
- Lack of desire to do anything (lethargy)
- Low blood pressure
- Significantly decreased urine output (or none)
- Sloughing of skin
- Twitching of facial muscles, arms, hands, legs, and feet
If the chemical is on the skin, remove it by washing the area thoroughly.
If the chemical was swallowed, seek medical treatment immediately.
If the chemical contacted the eyes, wash the eyes with cool water for 15 minutes.
Before Calling Emergency
Determine the following information:
- The person's age, weight, and condition
- The name of the product (ingredients and strength, if known)
- The time it was swallowed
- The amount swallowed
Your 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.
Take the container with you to the hospital, if possible.
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. Treatment depends on the individual symptoms. The person may receive:
- Airway support, including oxygen, breathing tube through the mouth (intubation), and breathing machine (ventilator)
- Blood and urine tests
- Camera down the throat (endoscopy) to see burns in the esophagus and stomach
- Chest x-ray
- ECG (electrocardiogram, or heart tracing)
- Fluids through a vein (IV)
- Medicines to treat symptoms
Note: Activated charcoal does not effectively treat (adsorb) boric acid.
For skin exposure, treatment may include:
- Surgical removal of burned skin (debridement)
- Transfer to a hospital that specializes in burn care
- Washing of the skin (irrigation), possibly every few hours for several days
The person may need to be admitted to a hospital for more treatment. Surgery may be needed if the esophagus, stomach, or intestine has a hole (perforation) from the acid.
The infant death rate from boric acid poisonings is high. However, boric acid poisoning is considerably rarer than in the past because the substance is no longer used as a disinfectant in nurseries. It is also no longer commonly used in medical preparations. Boric acid is an ingredient in some vaginal suppositories used for yeast infections, although this is NOT a standard treatment.
Swallowing a large amount of boric acid can have severe effects on many parts of the body. Damage to the esophagus and stomach continues to occur for several weeks after the boric acid was swallowed. Death from complications may occur as long as several months later. Holes (perforations) in the esophagus and stomach may result in serious infections in both the chest and abdominal cavities, which may result in death.
Aronson JK. Boric acid. In: Aronson JK, ed. Meyler's Side Effects of Drugs. 16th ed. Waltham, MA: Elsevier; 2016:1030-1031.
Hoyte C. Caustics. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 148.
Review Date 1/1/2021
Updated by: Jacob L. Heller, MD, MHA, Emergency Medicine, Emeritus, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.