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Potassium hydroxide poisoning

Potassium hydroxide is a chemical that comes as a powder, flakes, or pellets. It is commonly known as lye or potash. Potassium hydroxide is a caustic chemical. If it contacts tissues, it can cause severe damage, such as burning or ulcers, on contact. This article discusses poisoning from swallowing or touching potassium hydroxide or products that contain this chemical.

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.

Poisonous Ingredient

Potassium hydroxide

Where Found

Potassium hydroxide is found in:

  • Cuticle removal products
  • Drain cleaners
  • Leather tanning chemicals
  • Fertilizers
  • Herbicides
  • Paint removers
  • Button or disc batteries

Note: This list may not be all inclusive.

Symptoms

Symptoms from swallowing potassium hydroxide include:

  • Burns and severe pain in the mouth and throat
  • Throat swelling, which leads to difficulty breathing
  • Drooling
  • Severe abdominal pain
  • Diarrhea
  • Chest pain
  • Rapid drop in blood pressure (shock)
  • Vomiting, often bloody

Symptoms from getting potassium hydroxide on the skin or in the eyes include:

  • Burning
  • Severe pain
  • Vision loss

Home Care

Seek immediate medical help. DO NOT make a person throw up unless told to do so by poison control or a health care professional.

If the chemical is on the skin or in the eyes, flush with lots of water (at least 2 quarts or 1.9 liters) for at least 15 minutes.

If the chemical was swallowed, immediately give the person water or milk, unless instructed otherwise by a health care provider. DO NOT give water or milk if the person is having symptoms (such as vomiting, convulsions, or a decreased level of alertness) that make it hard to swallow.

If the person breathed in the poison, immediately move them to fresh air.

Before Calling Emergency

Determine the following information:

  • The person's age, weight, and condition
  • The name of the product (and ingredients and strength, if known)
  • The time it was swallowed or contacted
  • The amount swallowed or contacted

However, DO NOT delay calling for help if this information is not immediately available.

Poison Control

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.

What to Expect at the Emergency Room

The provider will measure and monitor the person's vital signs, including temperature, pulse, breathing rate, and blood pressure. 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 to see burns in the airway (bronchoscopy)
  • Camera down the throat (endoscopy) to see burns in the esophagus and stomach
  • Chest x-ray
  • CT (computerized axial tomography) scan
  • ECG (electrocardiogram, or heart tracing)
  • Fluids through a vein (IV)
  • Medicines to treat symptoms

Note: Activated charcoal does not effectively treat potassium hydroxide poisoning.

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 intestines have holes (perforations) from the chemical.

Outlook (Prognosis)

How well a person does depends on the amount of poison swallowed and how quickly treatment was received. The faster a person gets medical help, the better the chance for recovery.

Swallowing poisons can have severe effects on many parts of the body. Damage to the esophagus and stomach continues to occur for several weeks after the potassium hydroxide 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.

References

Hoyte C. Caustics. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 143.

Review Date 1/2/2023

Updated 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.