by Scholten A

Definition

A blister is a fluid-filled bump on the skin.

Blisters
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Causes

Blisters have many causes, such as:

  • Friction or constant pressure
  • Second-degree burns
  • Infections
  • Skin irritation from:
  • Certain cancers
  • Blistering diseases—such as epidermolysis bullosa, porphyria, or pemphigus
  • Autoimmune disorders

Risk Factors

Things that may increase the risk of blisters are:

  • Wearing ill-fitting shoes
  • Repetitive work with hand tools
  • Getting a sunburn or frostbite
  • Severe skin swelling, especially of the legs

Symptoms

Symptoms of a blister are:

  • A fluid-filled bump on the skin, which is often round
  • Fluid that is usually clear, but may be bloody, cloudy, or contain pus

Diagnosis

The doctor will ask about your symptoms and health history. A physical exam will be done. Blisters may be diagnosed on appearance.

Treatment

A blister will often heal without treatment. Sometimes the underlying cause needs to be treated.

Treatment options are:

  • Washing the area
  • Applying over-the-counter medicine—to ease itching and discomfort
  • Applying antibiotic ointment—to prevent or treat an infection
  • Bandaging the area—to protect it

Prevention

To lower the risk of a blister:

  • Wear shoes that fit properly. Always wear socks with your shoes.
  • Use gloves or protective padding when working with tools.
  • Wear a hat, protective clothing, and sunscreen when out in the sun.
  • Avoid skin contact with irritating chemicals or plants

RESOURCES

American Academy of Dermatology  https://www.aad.org 

National Institute of Arthritis and Musculoskeletal and Skin Diseases  https://www.niams.nih.gov 

CANADIAN RESOURCES

Canadian Dermatology Association  https://dermatology.ca 

Health Canada  http://www.canada.ca 

References

Abiad M, Kurban M, Abbas O. Recurrent blisters with pain following thermal burn injury to left leg and foot. Int J Dermatol. 2019;58(12):1377-1378.

Blistering skin conditions. DermNet New Zealand website. Available at: https://www.dermnetnz.org/topics/blistering-skin-conditions. Accessed January 29, 2021.

Blisters. Better Health Channel website. Available at: https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/blisters. Accessed January 29, 2021.

Blisters—causes. NHS Choices website. Available at: http://www.nhs.uk/Conditions/Blisters/Pages/Causes.aspx. Accessed January 29, 2021.

Blisters, calluses, and corns. Kids Health—Nemours Foundation website. Available at: http://kidshealth.org/en/kids/blisters.html. Accessed January 29, 2021.

Major burns. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/major-burns. Accessed on February 18, 2021.

Revision Information

  • Reviewer: EBSCO Medical Review Board Shawna Grubb, RN
  • Review Date: 09/2020
  • Update Date: 02/18/2021