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Definition

The popular term for a group of spots or red, inflamed skin that is usually a symptom of an underlying condition or disorder. Often temporary, a rash is only rarely a sign of a serious problem.

Description

A rash may occur on only one area of the skin, or it could cover almost all of the body. Also, a rash may or may not be itchy. Depending on how it looks, a rash may be described as:

• blistering (raised oval or round collections of fluid within or beneath the outer layer of skin)
• macular (flat spots)
• nodular (small, firm, knotty rounded mass)
• papular (small solid slightly raised areas)
• pustular (pus-containing skin blister)

Causes and symptoms

There are many theories as to the development of skin rashes, but experts are not completely clear what causes some of them. Generally a skin rash is an intermittent symptom, fading and...