Dandruff is a mild form of eczema on the scalp, where small flakes occur. This scaling is annoying, especially when flakes flutter down on dark apparel. Other symptoms of dandruff may be itching and a greasy scalp.

The flakes are old skin cells peel off the skin. The cells of the scalp renew itself constantly in about three weeks, the skin is renewed. At the bottom new cells are formed, at the top let the old cells loose in the form of a flake. These flakes are a normal skin small and invisible. Eczema of the scalp in the process of innovation is faster than normal and thus creates more flakes. Additionally keep the old skin cells clump together, causing the flakes are larger and more visible.

The term eczema is used for various skin lesions where the skin irritated, red, scaly and itchy. The form of eczema which causes dandruff is also known as seborrheic eczema. Another name for dandruff is seborrheic dermatitis of the scalp. The official medical term pityriasis capitis, the English term is dandruff.