A bruise is a traumatic injury of the soft tissues that results in breakage of the local capillaries and leakage of red blood cells. In the skin, bruising can be seen as a reddish-purple discoloration that does not blanch when pressed upon. This discoloration leads to the classic "black and blue" appearance. When a bruise fades, it becomes green and brown as the body metabolizes the blood cells and bilirubin pigment in the skin. A bruise can sometimes be associated with a temporary raised area in the skin and is usually associated with some tenderness. A bruise is best treated with local application of a cold pack immediately after injury. A bruise is medically termed a contusion. Bruises are typically a result of some degree of injury to the blood vessels in the skin. Easy bruising may be a result of a seemingly insignificant compression of skin or there may be no skin injury recollected. Easy bruising can occur when the blood vessels are weakened by diseases (such as scurvy), medications (such as aspirin, prednisone, and prednisolone), and aging. Easy bruising can also occur because of absent or deficient blood-clotting elements. Local leakage of blood into the skin from the capillaries that occurs spontaneously, without injury, and results in a flat, purplish discolored area is referred to as ecchymosis. Ecchymosis is usually not associated with tenderness.

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