Hair loss may be caused by baldness, seborrheic dermatitis, scarring alopecia and other diseases. If the cause is not clear, you can go to the dermatology department of the hospital. 1. Patchy baldness: the cause of patchy baldness has not been fully clarified, and it is mainly characterized by limited hair loss, and patients may not have any conscious symptoms. Patients may not have any conscious symptoms. They can go to the dermatology department of the hospital for consultation, and appropriate medication can be given under the guidance of the doctor. 2. Seborrheic alopecia: Seborrheic alopecia is hereditary and starts from puberty or late puberty. Seborrheic alopecia is a dermatologic problem and it is recommended to consult the dermatology department of a hospital. Minoxidil can be given under doctor’s supervision, which can promote hair growth. 3. Scarring alopecia: damaged scalp, necrosis of scalp cell tissues, hair loss, also belongs to dermatology, can be examined in the hospital dermatology department, if necessary, through the hair transplant surgery treatment. In addition to this, congenital factors, local infections, systemic diseases, physical factors, drugs, may lead to hair loss. It is recommended to go to the dermatology department of the hospital. If other diseases are suspected to be the cause, the dermatologist will suggest other departments such as endocrinology.