The scalp dandruff chunks can be gouged down for the following reasons: 1, head psoriasis: scalp and skin have their own metabolic cycle, metabolism will also have a small amount of dandruff when normal, but the chunks are very small and not easy to be found, when suffering from psoriasis the metabolic cycle of the scalp will be accelerated, with the hand grasp can be gouged down large pieces of dandruff, if the hair is separated at this time, can be found in the gouge down dandruff parts have large pieces of red spots. 2, scalp seborrheic dermatitis: increased oil secretion in the head, so that the scalp that should have been shed can not be shed in time, but a large number of piles together, and after a long time this part of the dandruff will thicken, so you can pick down large pieces of dandruff, according to the patient’s clinical performance, find the causative factors and actively treat the original disease, and this situation can naturally disappear after the original disease is cured.