There are many reasons for dandruff and itchiness, such as ringworm of the head, seborrheic dermatitis, poor hygiene, scalp psoriasis and so on. 1. Ringworm of the head: ringworm of the head is mainly related to fungal infection, which can show increased dandruff, itching and other phenomena. 2. Seborrheic dermatitis: seborrheic dermatitis is a chronic inflammatory skin disease, the cause of which is not yet clear, and may be related to the environment, heredity, malassezia breeding and other factors, and it occurs in the sebaceous glands in rich locations, such as the scalp, face, and may show more dandruff and itching. 3. Poor hygiene: usually don’t like to wash hair, don’t pay attention to personal hygiene, will lead to more dirt on the scalp, thus causing dandruff and itchy phenomenon. 4. Scalp psoriasis: scalp psoriasis will cause red patches on the scalp, patches covered with thick scales, accompanied by itching, which will lead to dandruff and itchy phenomenon. Caused by dandruff and itchy for many reasons, after the symptoms suggest that patients go to the hospital in a timely manner to improve the examination, a clear diagnosis, under the guidance of the doctor to take standardized treatment, do not ignore the symptoms, take it lightly.