Dandruff clumps can be picked off and grow repeatedly may be caused by psoriasis, ringworm of the head, seborrheic dermatitis and other reasons. 1. Psoriasis: the disease may be related to genetic, environmental, immune and other factors, head psoriasis will appear thicker scales, shedding will recur. 2. Tinea capitis: this disease is related to fungal infection, patients will have scaly lesions on the head, which are recurrent and may be accompanied by itching, hair loss and other symptoms. 3. seborrheic dermatitis: the disease may be associated with malassezia infection, sebum secretion abnormalities and other factors, scalp disease will appear chaff-like dandruff symptoms, recurring, with the progression of the disease may also appear vesicles, oozing and other symptoms. There are many factors that lead to dandruff clumps that can be picked off and grow repeatedly, and it is recommended that patients consult a doctor in a timely manner to identify the cause of the disease and then carry out the relevant treatment.