What triggers an attack of lupus in a susceptible person? Scientists have noted common features in many lupus patients. In some, exposure to the sun causes sudden development of a rash and then possibly other symptoms. In others an infection, perhaps a cold or a more serious infection, does not get better, and then complications arise. These complications may be the first signs of lupus. In still other cases, a drug taken for some illness produces the signaling symptoms. In some women, the first symptoms and signs develop during pregnancy. In others, they appear soon after delivery. Many people cannot remember or identify any specific factor. Obviously, many seemingly unrelated factors can trigger the onset of the disease.