Usually, the increase in dandruff after hair dyeing is not a normal phenomenon, but may be caused by infection, seborrheic dermatitis, dye cream stimulation, allergy, etc. 1.Infection: hair dyeing can easily cause fungal or bacterial infection, and fungal immunofluorescence testing is needed to rule out whether the increase in dandruff is caused by fungal infection; 2.Seborrheic dermatitis: seborrheic dermatitis exists in the dyer himself, and stimulation of local skin after hair dyeing can lead to repeated itching of the scalp, shedding of large pieces of skin flakes and increase in dandruff; 3.Dyeing cream stimulation: the time of hair dyeing is too long or the frequency of hair dyeing is too frequent, stimulating 4, allergy: some patients are allergic to hair dye, hair dye is mostly chemical substances, after dyeing hair, sweat impregnation, environmental comprehensive impact, resulting in hypersensitive reaction to the scalp, stimulating increased dandruff, itching, serious cases will also appear ooze, folliculitis, etc.; Therefore, if there is an increase in dandruff after hair dyeing, you can go to a regular hospital for relevant examination At the same time, do a good job of hair care in life, avoid using poor quality shampoo and avoid frequent perming and dyeing of hair.