A skin rash is a change in the color and/or texture of the skin. It can result from many different factors, including allergic reactions, friction, exposure to heat and moisture, infections, medications and contact with chemicals or other irritants.

In some cases, a patient will come into contact with an irritant or allergen that causes the skin to react. In other cases, an underlying medical condition – such as infection, infestation with parasites or disease – causes a rash to form on the surface of the skin. Skin rashes usually involve reddened skin that may be inflamed with blisters, bumps or pimples. They are sometimes itchy and may flake, scale, peel or weep fluid. Some may be painful or cause a stinging sensation. In severe cases, the rash may crack or bleed.