SLE is a kind of autoimmune disease that affects many systems of the body. It is found more often in young females. Clinically it has a variety of symptoms which occur repeatedly and tissues and organs like joints, muscles, skin and the kidneys are mostly involved. The cause of SLE is unknown, but generally it is believed to be related to heredity, virus infection, intake of some medicines, exposure to ultraviolet ray and disturbance of endocrine function.

SLE is considered to be of the category of "bi zheng"(arthralgia-syndrome), "yin yang du" (lupus erythematosus discoides), "gui lian chuang" (facial erythema). Insufficiency of congenital disposition, lack of nourishment after birth, or seven emotional upsets complicated by exposure to sunlight and attack of six exogenous factors are the causes of the disease; imbalance of yin and yang, stagnation of qi and blood and blockage of meridians are its pathogenesis. When toxic heat flares up the face, facial erythema occurs; when it deeply attacks yingfen and xuefen, the zang-fu organs are injured and complicated syndromes of the body ensue.