Dandruff is usually caused by Malassezia reproduction, seborrheic dermatitis, psoriasis and other diseases, and may also be caused by allergies to shampooing products, which can usually be washed with efficacious shampoos. If it is related to the reproduction of Malassezia, shampoo containing the following ingredients can be used, such as ketoconazole, selenium disulfide, etc., and anti-fungal sprays, such as biphenylbenzazole, can also be used. If associated with seborrheic dermatitis, shampoos containing ingredients such as coal tar, ketoconazole, and selenium sulfide may be used. If related to psoriasis, corticosteroid ointment, retinoic acid cream, carbotriol, etc. can be used to apply scalp, for erythrodermic type, pustular type can be used for a short period of time, such as methotrexate, salicylate and other medications. Drug treatment needs to be under the guidance of a doctor, especially hormonal drugs.