There are several possibilities for scalp crusting: 1. Ringworm caused by fungal infection can appear as a rash with crusting, flaking, and dark red spots, accompanied by a certain amount of itching. In clinical treatment, you can apply topical terbinafine hydrochloride spray, combined with miconazole nitrate ointment application treatment. If more serious, you can take oral itraconazole capsules for treatment; 2, seborrheic dermatitis, mainly in addition to crusting can also appear erythema, desquamation, papules such rash. In the clinic is mainly due to allergies, infections, or lack of vitamins and other factors, can be oral levocetirizine hydrochloride capsules, topical trimethoprim ointment application treatment.