Large dandruff on the hair may be caused by physiological factors such as impure scalp; it may also be caused by diseases such as head simple furuncle and seborrheic dermatitis of the scalp. Patients can follow the doctor’s instructions according to the different causes of dandruff to choose the appropriate treatment, such as general treatment, drug treatment and so on. 1. Physiological factors: If you don’t wash your hair often and use unclean towel to wipe your head, it may lead to unclean scalp and large dandruff. This is a normal physiological phenomenon, and it is recommended to follow up with regular hair washing to keep the head clean and dry, and avoid scratching the scalp in the near future. 2. Head simple chaff rash: If there are large pieces of dandruff on the hair due to head simple chaff rash, patients can use salicylic acid ointment, sulfur ointment and other topical agents to play the role of exfoliation and reduce the production of scales. 3. Seborrheic dermatitis of the scalp: If there is a large piece of dandruff on the hair due to seborrheic dermatitis of the scalp, patients can use salicylic acid lotion, selenium disulfide lotion and other topical preparations of drugs to achieve the effect of anti-inflammatory, dissolving lipids. If the degree of scalp inflammation is more serious, you can use hydrocortisone cream and other glucocorticoid drugs to achieve anti-inflammatory effect. If there is a large piece of dandruff on the hair, after excluding physiological factors, patients can go to the hospital, clear cause of the disease and choose the appropriate way of treatment.