Solar Purpura · What Is It, Appearance, Causes, and More

Solar purpura is a common skin disorder characterized by easy bruising that results in the appearance of flat, purple patches, associated with extensive sun exposure. Solar purpura is more commonly known as senile purpura, as it mostly affects older individuals, but is also sometimes called actinic purpura or Bateman purpura.  

Purpura occurs when red blood cells leak from blood vessels into the skin, creating a discolored area that is larger than 3 millimeters (about 0.04 inches). In contrast to eczema or allergic reactions, purpura does not blanch (i.e., turn white) with pressure, nor is it tender or itchy. Although the appearance of solar purpura may be bothersome to some, the disorder is typically not dangerous.  

Solar purpura is most likely caused by many years of ultraviolet (UV) radiation exposure from sunlight. Long-term exposure to UV light can damage the skin connective tissue; as a result, even minor trauma can cause blood vessels to burst, creating the characteristic skin discoloration of solar purpura.  

Solar purpura may also be caused by zinc deficiency, as zinc is a mineral necessary for wound healing. Additionally, common blood thinners (e.g., aspirin) reduce blood clotting, which can result in increased bleeding after a minor trauma and the formation of larger areas of purpura.