solar purpura solar purpura solar purpura (also known as "actinic purpura," and "senile purpura") is a skin condition characterized by large, sharply outlined, 1- to 5-cm, dark purplish-red ecchymoses appearing on the dorsa of the forearms and less often the hands. solar purpurasenile purpuraspecialtydermatology the condition is most common in elderly people of european descent. it is caused by sun-induced damage to the connective tissue of the skin. no treatment is necessary. the lesions typically fade over a period of up to three weeks.