Symptom Checker: Symptoms & Signs Index
Medical Author: Melissa Conrad Stöppler, MD
Blisters are small raised areas that are filled with fluid and located in the superficial layer of the skin. They look like bubbles on the surface of the skin. Although they are often caused by irritation or friction (such as with a poorly fitting shoe), blisters can also represent disease processes. Blisters can accompany some types of skin rashes and inflammatory conditions, including certain autoimmune diseases. Depending upon the cause of the blisters, blisters may occur singly or in groups. In contrast to abscesses and boils, which are collections of inflammatory fluid found deep in the tissues, blisters are found in the most superficial layer of skin.
Small fluid-filled blisters are medically known as vesicles. Bullae (singular = bulla) are blisters that are larger than 1 cm across.
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Fauci, Anthony S., et al. Harrison's Principles of Internal Medicine. 17th ed. United States: McGraw-Hill Professional, 2008.
Causes of Blisters
In This ArticleBoils Article
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In This ArticleBullous Pemphigoid Article
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In This ArticleBurns (First Aid) Article
- Introduction to burns
- How are burns classified?
- What is the significance of the amount of body area burned?
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In This ArticleChickenpox (Varicella) Article
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In This ArticleCuts, Scrapes and Puncture Wounds Article
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In This ArticleEczema Article
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In This ArticleFolliculitis Article
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In This ArticleFrostbite (Cold Weather-Related Injuries) Article
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- Introduction to frostbite and cold weather-related injuries
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- Trench foot
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In This ArticleGenital Herpes in Women Article
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In This ArticleHand Foot and Mouth Disease Article
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In This ArticleIs Shingles Contagious? Article
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- Is shingles contagious?
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- How long is shingles contagious?
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In This ArticleLichen Sclerosus Article
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In This ArticleNecrotizing Fasciitis Article
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In This ArticleRash Article
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Other Causes of Blisters
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