Large dandruff on the head may be due to seborrheic dermatitis, psoriasis and other factors, the need to clarify the cause of the disease, targeted treatment, common treatment drugs such as ketoconazole. 1. Seborrheic dermatitis: inflammatory seborrheic dermatitis will be covered with greasy flakes on the erythema, yellow or brown scabs, accompanied by vesicles, oozing and other symptoms. Depending on the condition, shampoo containing tar, zinc pyrithione or ketoconazole can be used to wash the hair, or use ketoconazole, miconazole and other medications. 2. Psoriasis: The scalp scales of psoriasis patients are thicker, often beyond the hairline, symmetrical, and the hair is in bundles, which can be accompanied by itching. Salicylic acid, ketoconazole, coal tar and other detergents can be used to wash the hair, while paying attention to scalp cleaning, light diet, avoid eating spicy, stimulating food. Large dandruff on the head may also be caused by other factors such as scalp furuncle, it is recommended that the patient seek medical attention in a timely manner, under the guidance of the doctor for relevant examinations, in order to clarify the cause of the disease, symptomatic treatment, and to avoid the use of private medication, so as to avoid delays in the condition.