Hair needs to see a dermatologist, because hair belongs to the skin appendages among the organs of the human body, so hair diseases need to go to a dermatologist. Hair disease, whether it is gray hair or hair loss, and hair texture changes, usually through the dermatologist, through the local or systematic testing to diagnose the disease, and then according to the specific manifestations of the disease to target the use of drugs. First of all, alopecia areata can be clinically categorized as patchy baldness, seborrheic alopecia or alopecia areata, etc. It is also possible that the alopecia areata may be secondary to skin infections, such as alopecia areata formed by fungal infections or alopecia areata formed by lichen planus, or alopecia areata formed by sexually transmitted infections, such as syphilis. Therefore, the specific causes of hair loss and treatment modalities need to be determined by a dermatologist to target the medication.