Modern dermatology is finding evermore evidence for the opinion that one of the most important conditions for proper skin function is a balance between proliferation and differentiation of epithelial cells. A manifestation of such disturbance is dandruff - pityriasis sicca and pityriasis steatoides - localized in the scalp or in the eyebrows. This banal but psychosocially disturbing disorder is connected not only with internal factors such as atopic diathesis, but also with external factors such as tobacco smoke-laden premises and stressing situations in life. The importance of microbes is undoubted and therefore even therapy has to be aimed in that direction, namely the application of zinc pyrothione. Microbes induce an immune reaction not as infectious agents, but as producers of secondary inflammatory cytokins. Significant is the damage to the epidermal permeable barrier, which allows for other unexpected complications.

        Key words: hais - pityriasis - dandruff - barrier - Malassezia.