Male pubic hair loss in large quantities may be related to bad habits, but also may be the emergence of baldness, drug effects and other diseases. 1. Bad habits, male patients usually work under pressure, poor sleep quality may cause changes in the growth cycle of hair follicles, hair shedding, male pubic hair loss. 2. Pemphigus vulgaris, pemphigus vulgaris belongs to autoimmune diseases, some patients appear pemphigus vulgaris may lead to hair follicle tissue damage, the emergence of pubic hair loss symptoms. 3. Drugs, if often exposed to certain drugs, such as chemotherapy drugs, may lead to abnormal metabolism of hair follicle tissue, hair follicles ischemia and lack of oxygen, hair can not grow normally, appearing in the male pubic area of a large number of hair loss. If frequent hair loss, need to pay attention to, timely medical treatment.