The cause of baldness is not entirely clear, but may be related to genetic, immune, emotional and endocrine factors. If all the hair is lost, it is called total baldness, and if all the hair on the body is lost, it is called general baldness. The disease can be seen in young adults. The clinical manifestation is the sudden occurrence of a variable number of round or oval shaped hair loss on the scalp with smooth skin without inflammation or scaling; if the number of lesions increases, they may fuse with each other to form large patches. Most patients enter the recovery period after more than 3 months of onset, with the earliest appearance of fine, soft, light-colored vellus hairs, gradually thickening and darkening, and finally returning to normal. Most patients can heal spontaneously, but half of them can relapse, and those with early onset and extensive hair loss areas are prone to relapse; a few patients with total and general baldness do not heal after years of treatment. Nail changes can occur in pemphigus vulgaris. Cloudy and brittle nails can occur. Unifocal Alopecia areata: It accounts for one-fifth of the total number of alopecia areata and is characterized by a single area of hair loss, often without conscious symptoms. Multifocal baldness: Multiple isolated areas of hair loss occurring within a few months or weeks is called multifocal baldness. Clinical treatment is to remove possible triggering factors and pay attention to the combination of work and rest. Oral treatment with glucocorticoids For rapid and extensive hair loss including alopecia totalis and alopecia universalis, oral prednisone can be administered. After the disease is stabilized, the dosage is gradually reduced and maintained for several months, but some patients are prone to relapse after stopping the drug, and the side effects of glucocorticoids can occur with long-term application. Cystine and vitamin B6 have auxiliary therapeutic effects; intracutaneous drug injections can be used for stubborn lesions. In addition, helium-neon laser irradiation, audio electrotherapy, photochemotherapy, etc. can also be used.