Hair loss should be seen in dermatology, because hair is also a skin appendage, in addition to skin there are more skin appendages, such as hair, sebaceous glands, hair loss for more reasons, as follows: 1, baldness: that is, suddenly less piece, can also be the entire hair bald, called total baldness. Total baldness and patchy baldness are mainly due to some immune cells inside the skin attacking the hair roots, which should be treated according to the patchy baldness method; 2. Rising hairline: some people have shedding called male pattern baldness, although it is called male pattern baldness, it happens to both men and women. This disease is related to androgens. This kind of hair loss should be inhibited by androgens, and can be treated with oral medication to inhibit androgen receptors. Because there are many androgen receptors on the hair, if the oral intake of such drugs can be inhibited, but also can be used to promote hair growth drugs such as minoxidil, can treat male pattern baldness.