Itchy scalp the next day after washing hair may be related to ringworm, seborrheic dermatitis, contact dermatitis and other diseases, in the treatment of antifungal, lipolytic and anti-allergic treatment. 1. Tinea capitis is a disease caused by infection of the scalp with ringworm, which is characterized by itchy skin and scaling, as well as hair loss and breakage. In the treatment of tinea capitis, anti-fungal drugs are mainly given, such as topical ketoconazole lotion and oral fluconazole dispersible tablets, etc. The treatment of seborrheic dermatitis may be related to seborrheic dermatitis and contact dermatitis. 2. The cause of seborrheic dermatitis is not yet clear, may be related to genetics, microbial local infections, etc., in the clinic can be manifested as greasy hair, greasy scales, and itching, etc., in the treatment of the main topical lipolytic drugs, such as topical selenium disulfide lotion. 3. Contact dermatitis is an allergic reaction of the scalp due to contact with allergenic substances, mainly manifested as scalp itching, erythema, papules, etc., common allergens are shampoo, hair dye, and the treatment mainly involves the administration of antihistamine drugs, such as oral loratadine tablets. Due to the different causes of the disease, the treatment program is different, the specific situation needs to first ask the doctor for an interview, and then according to the actual situation of the choice of drug treatment.