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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- What are symptoms of bullous pemphigoid?
- How is bullous pemphigoid diagnosed?
- What is the treatment for bullous pemphigoid?
- What is the prognosis of bullous pemphigoid?
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?
- What about electrical burns?
- What about chemical burns?
- First aid for burns
In This ArticleChickenpox (Varicella) Article
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- What are chickenpox symptoms and signs?
- What are treatment options for chickenpox?
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In This ArticleCuts, Scrapes and Puncture Wounds Article
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- What is the best first aid for a cut or scrape?
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In This ArticleDiaper Rash Article
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In This ArticleEczema Article
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In This ArticleFolliculitis Article
- Folliculitis facts
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- Who develops folliculitis?
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In This ArticleFrostbite (Cold Weather-Related Injuries) Article
- Frostbite and cold weather-related injuries facts
- Introduction to frostbite and cold weather-related injuries
- What type of injuries can be caused by cold weather?
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- What are cold weather-related injuries without tissue freezing?
- Trench foot
- Frostbite: Cold weather-related injuries with tissue freezing
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In This ArticleGenital Herpes in Women Article
- Genital herpes in women facts
- What is genital herpes?
- What causes genital herpes?
- How is genital herpes transmitted?
- What are the signs and symptoms of genital herpes?
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In This ArticleHand Foot and Mouth Disease Article
- Hand foot and mouth (HFM) disease facts
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- What causes hand foot and mouth disease?
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In This ArticleIs Poison Ivy Contagious? Article
- What is poison ivy?
- Is poison ivy contagious?
- What is the incubation period for a poison ivy rash?
- Is it possible for a poison ivy rash to spread?
- How long does a poison ivy rash last?
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In This ArticleIs Shingles Contagious? Article
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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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In This ArticleShingles Article
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Other Causes of Blisters
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