There are white patches of dandruff on the scalp, consider the following disease possibilities: 1, common psoriasis: mainly due to infection or trauma, genetics and other factors. In terms of treatment, you can apply topical application of carbotriol, apply hydrocortisone butyrate ointment after application, and take oral treatment with compound amineptin tablets and compound glycyrrhizin tablets. 2. Erysipelas: It may be due to chronic eczema, common psoriasis, hair red furuncle, lichen planus and other diseases, after unreasonable medication stimulation, triggered by the appearance of diffuse, flushed, swollen rash around the body, with patches of scalp parts White dandruff. In terms of treatment, it is necessary to administer compound glycyrrhizic acid monoamine S sodium chloride injection and also to apply zinc oxide ointment borate in combination.