Bullous pemphigoid.

B ullous pemphigoid is an autoimmune disease, which means that the cells in the body that normally fight infection attack the body instead. The body’s immune system is confused and makes an antibody (type of protein used to fight infection) that targets a part of the skin that normally holds it together. The attack on the skin causes blisters (firm, fluid-filled bubbles on the skin) to form. This disease most often involves only the skin, but the eyes, mouth, and genitals also can be affected. In most cases, the disease develops on its own, but certain medications also can cause bullous pemphigoid to develop. Bullous pemphigoid commonly affects people older than 60 years but can occur in younger people. Once someone is diagnosed as having this disease, they can have it for many years. Treatment helps to control the disease, but there is no permanent cure.