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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- How is bullous pemphigoid diagnosed?
- What is the treatment for bullous pemphigoid?
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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?
- How important is the location of a burn?
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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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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 ArticleImpetigo Article
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In This ArticleLichen Sclerosus Article
- Lichen sclerosus facts*
- What is lichen sclerosus?
- Who gets lichen sclerosus?
- What are lichen sclerosus symptoms and signs?
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In This ArticleNecrotizing Fasciitis Article
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In This ArticlePoison Ivy Article
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In This ArticleRash Article
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In This ArticleShingles Article
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Spider Bites (Including Black Widow and Brown Recluse) The majority of spiders in the United States are harmless. Two exceptions include the black widow spider and the brown recluse...learn more »In This ArticleSpider Bites (Including Black Widow and Brown Recluse) Article
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Other Causes of Blisters
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